[Editor’s Note: Commentaries on the Book of Moses and Genesis Chapters 1 – 10 may be found on the ScripturePlus App from Book of Mormon Central and on the Bible Central website here.]
Genesis 18–20 Overview. Abraham’s Welcome, Sodom’s Wickedness, and Abimelech’s Repentance
In these three chapters, we encounter the story of Abraham’s welcome of the three visitors who will confirm and definitively announce the arrival of his long-awaited son Isaac. Then, after Abraham pleads to the Lord to spare Sodom and Gomorrah from destruction, the messengers proceed to these notorious cities to see the situation for themselves—at the same time testing Lot’s family to see how their welcome and faithfulness compares to that of Abraham and Sarah. Finally, in chapter 20, we meet Abimelech, the second king in Genesis who aspired to take Sarah to wife.
A key to understanding what ties all three of these stories together is the Hebrew verb yāda‘—to know—and the related noun da’at—knowledge. After a brief exploration of the rich and powerful meanings of these terms in Hebrew, we will look carefully to see how they apply in Genesis 18–20.
In the Bible, yāda‘ and da’at combine two Hebrew concepts: knowing something with the mind and heart and knowing something physically. When used to talk about people, it implies a relationship; when God or a marriage partner is involved, it often implies a covenant relationship. These two terms appear twenty-two times in the first twenty chapters of Genesis, and, significantly, eight of these occur within these three chapters.
The first biblical appearance of the Hebrew terms for knowing is in Genesis 2:9, when we are introduced to the tree of knowledge of good and evil. The French Bible scholar André Chouraqui translated this as the “tree of penetration of good and evil.” The English word “penetration” is a helpful English translation because it expresses simultaneously both the intellectual and physical meanings of the original Hebrew term. In other words, when Adam and Eve transgressed they not only cognitively “penetrated” the tree (in the old English sense of “gaining intellectual or spiritual access”) when they obtained the insights that resulted from eating the fruit, but also physically “penetrated” the sacred, symbolic boundary of the garden where the tree was planted so as to pluck its fruit.
After the story of the Fall, the next appearance of the word is in Genesis 4:1, when “Adam knew Eve his wife” and their son Cain was conceived (emphasis added). Because Adam and Eve were faithful to their covenants, their act of mutual knowing was not only physical but also covenantal in nature. Indeed, the act itself honored their covenants with God to “cleave” together as one and to “multiply and replenish the earth” (Genesis 1:28; 2:24). Indeed, a happy covenantal marriage relationship is often used in scripture as a model of the covenant relationship between God and His people. As a husband and wife strive to be “one” in all things, so those who keep their covenants with God strive to “know” Him and become “one” with Him (John 17:3, 20–23; 1 Corinthians 6:17).
With similar symbolism, in Jesus’ account of the final judgment (see JST Matthew 7:31), He described the tragedy of those who, by unfaithfulness to their covenants, alienated themselves from His love. Said He to them, “I never knew you” (Matthew 7:21–23). By this, we are meant to understand that the Lord knows only those individuals who have received and kept His covenants. Elder Bruce R. McConkie further explained:
Jesus is saying: “Ye never knew me so fully as to be sealed up unto eternal life with your callings and elections made sure, and since you did not magnify your callings in the priesthood, you shall be cast out and be as though I never knew you.”
By way of analogy to the Jewish law specifying that an “advocate cannot represent a client whom he or she does not know personally,” Jesus is saying that He cannot act as a Mediator for such a person, and that if, on that day of final judgment (JST Matthew 7:31) they are found to have “[wasted] the days of [their] probation” (2 Nephi 9:27), they must therefore be “cast out” from His presence.
With the understanding of the covenant meaning of yāda‘ as background, we can better appreciate what the Lord said of Abraham in Genesis 18:19: “For I know him, that he will command his children and his household . . . and they shall keep the way of the Lord.” By way of contrast, Lot, “Abraham’s nephew (Genesis 12:5) who, at first and laudably, joins his uncle in the latter’s wanderings but, finally and less laudably, settles among the worst evildoers [that is, in Sodom], is quite an ambivalent figure and therefore rightly called Lot, [from the Hebrew word for] ‘veiled.’” In the context of the events of Genesis 19, Lot’s “veiling” signified, among other things, that, unlike Abraham, he had cut himself off from divine knowledge and, going further, suggested that at the last day he would not be received into the presence of the Lord. Finally, in a physical sense, after his daughters incestuously “la[id] with” their father. (Note that scripture deliberately avoided describing their act with the Hebrew covenantal word for “knowing” in this sense.) The inspired author underlined the same lesson when it said that Lot was drunken and “perceived [yāda‘] not” what his daughters had done (Genesis 19:33, 35).
By the time we reach chapter 20, we are prepared by these previous stories to understand that King Abimelech, who was not then part of Jehovah’s covenant people, was more righteous than Lot, who forsook the covenant he had been privileged to receive. For, despite Abimelech’s grievous offense in kidnapping Sarah to become one of his harem, God freely forgave him, saying to him in a dream: “I know that thou didst this in the integrity of thy heart” (Genesis 20:6). The God that Abimelech did not know knew him. Afterward, Abraham prays for Abimelech and his household is blessed (Genesis 20:17–18).
With these three stories as an introduction to the Old Testament concept of “knowing,” we are prepared for chapters 21 and 22 where Abraham will come to know God through a supreme test of faith. His trial reminds us of the stirring account of handcart pioneer Francis Webster: “We became acquainted with [God] in our extremities.” Through Abraham’s near-sacrifice of Isaac, he came to understand firsthand the depth of love described in John 3:16: “For God so loved the world, that he gave his only begotten Son, that whosoever believeth in him should not perish, but have everlasting life.”
Adapted from Abraham’s Hebron: Then and Now: 05-Mamre, https://www.youtube.com/results?search_query=bradshaw+abraham+in+hebron+mamre (among other things, the end of this video features Hugh Nibley recounting the story of Abraham’s encounter with the three messengers in Genesis 18).
Genesis 18–20 chapter headings
Genesis 18:1–8. Abraham’s Character Is Revealed in His Lavish Hospitality to Strangers
18:1. And the Lord appeared unto him in the plains of Mamre: and he sat in the tent door in the heat of the day. Rabbinical commentary takes great care to depict the extraordinary nature of Abraham’s hospitality to all travelers which, in his hundredth year, was rewarded by the visit of these three messengers from God. As in many other such accounts, his blessings came only after a period of intense trial.
On the third day after his circumcision (see Genesis 17:23–27), when Abraham was suffering dire pain, God spoke to the angels, saying, ‘Go to, let us pay a visit to the sick.’ . . . The day whereon God visited him was exceedingly hot, for He had bored a hole in hell, so that its heat might reach as far as the earth, and no wayfarer venture abroad on the highways, and Abraham be left undisturbed in his pain. But the absence of strangers caused Abraham great vexation, and he sent his servant Eliezer forth to keep a lookout for travelers. When the servant returned from his fruitless search, Abraham himself, in spite of his illness and the scorching heat, prepared to go forth on the highway.
Hugh Nibley, who was moved by this story, said of Abraham: “He seemed to be generous to the point of lacking common sense.” Remember that Abraham was one hundred years old, sick, and sitting in pain when he rose and ran to welcome the visitors. “‘Lord of the Universe,’ he cried, recognizing one of them, ‘is it the order of the Cosmos that I sit while you remain standing?’ The scene, as . . . André Parrot . . . remarks, ‘is as magnificent as it is strange.’”
The hospitality of Abraham is commemorated annually by the Jewish people on the first night of Sukkot (the feast of tabernacles or booths). On that night, it is said that Abraham himself sometimes appears in the booths of the righteous, followed on successive nights by six other “shepherds” of Israel, the uspizim. Those so privileged are invited to emulate the virtues of their visitors, Abraham’s primary virtue being kindness. “Since the world was created for kindness, Chazal states that the world was created for Avraham, for it was built in his merit.”
18:2. three men. In line with Doctrine and Covenants 29:42–43, some ancient texts also speak of three messengers who appeared to warn, protect, and instruct Adam and Eve, and of how their efforts were resented and opposed by Satan. For example, in the early Christian Apocalypse of Adam we read, “And I saw before me three men whose appearance I could not recognize . . . saying to me, ‘Rise up, Adam, from the sleep of death, and hear about [the manifestation of God] and the seed of that man to whom life has come.’” Similar accounts are also given concerning other prominent Old Testament figures, including Abraham. With reference such messengers, BYU professor Alonzo Gaskill observed that:
Peter, James, and John, whether appearing [literally or figuratively] to Adam and Eve or serving as the head of the post-resurrection Church in the meridian of time, are symbols of something much greater than themselves, namely, the Godhead . . . as [are] all subsequent First Presidencies. . . . What is of importance is what they brought and whom they represented. 
18:2–8. he ran to meet them . . . and bowed himself toward the ground. Textual details imply that Abraham was not giving the three men special treatment because he knew they were divinely sent, but rather extended the same lavish bounty that he would have to any stranger. Unlike Abraham, scripture readers, of course, already know that the messengers represent the Lord.
Summarizing the extent of Abraham’s welcome to the strangers, Nahum Sarna writes,
Abraham’s openhearted, liberal hospitality to the total strangers knows no bounds. He has water brought for them to bathe their feet, a much appreciated comfort to the traveler. . . . He invites them to rest under “the tree.” . . . He promises to fetch “a morsel of bread” but prepares a lavish feast. . . . In asking Sarah to bake cakes, Abraham specifies the use of “choice flour,” that is, the finest and choicest of wheat flour, the type from which meal offerings were later brought to the sanctuary. [André Chouraqui calculates the “three measures of fine meal” (v. 6) as amounting to forty liters!] [Abraham] himself selects the calf for the main dish, a rare delicacy and a sign of princely hospitality among pastoralists. He provides curds and milk, the basic products of a pastoral economy. . . . Milk was highly esteemed in the ancient Near East and was offered to the gods. . . . Abraham personally serves the strangers this rich fare and stands close by, ready to attend to their needs.
Adapted from FIRST DAYS, p. 116.
Genesis 18:9–15. The Announcement about Sarah Heralding Isaac’s Birth
18:9. Where is Sarah thy wife? The fact that the strangers already knew Sarah’s name is the first hint to Abraham that these were no ordinary men.
18:12. Sarah laughed within herself. The Hebrew verb yitsḥaq, “to laugh,” is identical to the Hebrew form of the name Isaac that was introduced in Genesis 17:19. In chapter 17, Abraham had laughed at the idea that Sarah would bear a son. Now Sarah laughs with him. References to laughter occur four times in the span of a few verses (vv. 9, 12, 13, 15).
18:12. pleasure. The Hebrew term ‘ednu is related to Eden and conveys the idea of agricultural bounty (hence, the Book of Mormon alludes to “Eden” in the place-name “Bountiful”). A better translation of Sarah’s expression would be “fruitfulness, abundance”—that is, pregnancy.
18:15. Is any thing too hard for the Lord? President Spencer W. Kimball’s firm answer to this question was, “I believe the Lord can do anything he sets his mind to do.” However, qualifying his answer to teach a broader lesson, he said, “But I can see no good reason why the Lord would open doors that we are not prepared to enter.”
Abraham and Sarah had been preparing for the arrival of Isaac for decades, and it was only then that God found them ready for this blessing. Nahum Sarna notes the fashion in which “the divine promise has been unfolding in stages,” saying,
First, in 15:4, Abraham was assured that his heir would be a natural-born son; then, in 17:16–21, he was assured that Sarah would bear this child; now a time limit is set for the fulfillment of the promise. 
The Announcement about Sodom (18:16–22)
18:16. Abraham walking along with them to see them off. We are meant to understand that Abraham’s hospitality continued to the very end of the visit. The verse also provides a pause in the narrative where God outlined the reasons behind His intentions for Sodom to Abraham.
18:19. For I know him, that he will command his children and his household . . . and they shall keep the way of the Lord to do justice and judgment. Perceptively, Robert Alter paraphrases the literal Hebrew phrase “For I know him” to read “For I have embraced him.” The terms “justice” (tsedeq “righteousness”) and “judgment” (mishpat “justice”) were repeated as part of Abraham’s pleas to the Lord to spare any righteous residents of Sodom.
According to Nahum Sarna, Abraham was granted the “singular privilege” of knowing God’s intentions “because he symbolizes the future Jewish nation, which is destined to become a source of blessing to other nations. As such, he cannot avoid direct involvement in the fortunes of humanity at large.’” God welcomed Abraham’s desire to “reason” with Him (compare Isaiah 1:18, Doctrine and Covenants 50:10). The dialogue will be another demonstration that Abraham’s kindness is not self-serving, but extends freely to all, in likeness of the Father’s parental concern. Abraham passes this test with flying colors.
18:20. their sin is very grievous. What were the sins of Sodom? Jeremiah 23:14 cites “adultery, false dealing, and the encouragement of evildoers,” while Ezekiel sums up the situation as follows in 16:49: ‘Only this was the sin of your sister Sodom: arrogance! She and her daughters had plenty of bread and untroubled tranquility; yet she did not support the poor and the needy.’ … The indictment of Sodom lies entirely in the moral realm, there is no hint of . . . idolatry. As with the Flood story, the Sodom and Gomorrah narrative assumes the existence of a universal moral law that God expects all humankind to follow.”
Modern readers will notice the obvious omission in the list above, namely, acts of homosexual behavior between men. Genesis 19 indicates that the men of the city of Sodom intended to engage in homosexual acts with Lot’s guests, something explicitly condemned in Leviticus 18:22; 20:13. However, a 2021 article by Stephen O. Smoot provides a helpful corrective to discussions that feature an almost exclusive emphasis on the purely sexual dimension of the Sodomites’ depravity. While the intention to “humiliate foreign visitors through a heinous act of sexual violence” “was a clear component of the sin of Sodom,” the focus of the narrative in its larger context is on the contrast between Abraham’s charity for all and the general lack of human decency of the men of Sodom, especially toward the poor and the stranger.
18:22. Abraham stood yet before the Lord. The verse provides a second pause in the narrative where Abraham’s silent standing hints that he was considering how to express his concerns for the righteous in Sodom, notably the family of his own nephew. It seems that the foremost of the three messengers, here named as “the Lord,” conversed with Abraham while the two other messengers had apparently already gone to Sodom to begin a firsthand investigation “to see whether they have done altogether according to the cry of it” (Genesis 18:21).
18:32. Peradventure ten shall be found there. Ronald S. Hendel comments about the dialogue between Abraham and the Lord, saying,
With great diplomacy and humility, [Abraham] argues that God must be just (v. 23), and even more that God must be merciful (v. 24). When God grants Abraham’s plea (v. 26), Abraham presses his advantage and in a remarkable rhetorical exchange talks God down from fifty righteous to ten (v. 32). There is an element of humor in the Middle Eastern custom of haggling, here not over the price of goods, but the proper balance of justice and mercy and the fate of Sodom. As it happens, Abraham prevails in establishing the right moral principle, but God still destroys the cities, since of all of its inhabitants only Lot and his immediate family are not wicked.
Genesis 19:1–11. Lot’s Family, the Messengers, and the Sodomites
19:1. When Lot saw them, he rose to meet them. About Lot’s gradual transformation from an outsider to a city dweller in Sodom, Nahum Sarna writes,
Lot lived formerly in a tent “near Sodom” (13:12). Now he has become a townsman and resides in a house inside the city (compare vv. 4, 10ff.). Although he has changed his style of life, he still preserves the virtue of hospitality.
But contrasting the conventional nature of Lot’s welcome to the extravagant efforts of Abraham to assure the comfort of his guests, Ronald S. Hendel writes,
Lot’s hospitality to the strangers, although genuine, is not as gracious as Abraham’s in the previous chapter (18:1–8). Whereas Abraham ran . . . to meet them, Lot rose to meet them. Whereas Abraham served cakes of choice flour, Lot served unleavened bread. Whereas Abraham stood by them . . . while they ate, at Lot’s feast they ate together: and they ate. These are subtle denigrations of Lot by comparison with Abraham.
19:2. My lords. In verse 2, the contrast between Abraham and Lot continued. While Abraham seemed to recognize the strangers as divine early on in his encounter, Lot was slow to understand who they represented. According to Brian Doyle,
The differences serve to distinguish the characters of Abraham (daylight, he sees/understands, he addresses his visitors as “My Lord”) and Lot (darkness, lack of understanding, addresses his visitors as “my lords”).
Remember that the name Lot is related to a Hebrew root that signifies “wrap closely, tightly, enwrap, envelop,” and has the meanings of “covering; veil; covered; concealed; myrrh.” The name seems to be related to the character of Lot who, in contrast to Abraham, had no access to hidden, divine knowledge of who the visitors were and what God intended to do.
19:5. Where are the men which came in to thee this night? Bring them out unto us, that we may know them. The context and phrasing strongly indicate the intention of the men to commit homosexual rape. However, there may be even more to the story. Brian Doyle’s exegesis of Genesis 18–19, he argues that the key Hebrew term in the story (pethakh “door”) “is a point of access, a place of encounter with the divine, associated with the Tent of Meeting and the Temple.” The righteous are admitted through this door, whereas the wicked are excluded. Summarizing the contrasts among Abraham, Lot, and the men of the city, he writes,
Abraham recognizes immediately and gains access to the divine; Lot gets off to a poor start but the ‘veil’ cloaking his understanding is gradually lifted as he is brought into the presence of the divine, thus allowing him to express recognition thereof later in the text; the people of Sodom ultimately recognize the divine presence but their response echoes their character—a proud and greedy demand to have access to the manifest divine presence that would have been little more than ridiculous to the narrative’s earliest audience.
Though Doyle probably goes too far in insisting that yāda‘ has no sexual connotation in the Sodom story, his arguments support the idea that yāda‘ may include the idea of spiritual ignorance in addition to its allusion to sexual misbehavior.
19:9. And they were angry with him. The italicized words below were added or revised in the Joseph Smith Translation of Genesis 19:9–12. Among other things, the modifications strengthen the interpretation that the threat of the men was sexual in nature.
9 And they said unto him, Stand back. And they were angry with him.
10 And they said among themselves, This one man came in to sojourn among us, and he will needs now make himself to be a judge; now we will deal worse with him than with them.
11 Wherefore they said unto the man, We will have the men, and thy daughters also; and we will do with them as seemeth us good.
12 Now this was after the wickedness of Sodom.
19:8. Behold now, I have two daughters. The italicized words below were added or revised in the Joseph Smith Translation of Genesis 19:13. Among other things, the modifications strengthen the description of Lot’s moral resistance to the men’s entreaties and reinforce the idea that the men are both “angels of God” and “holy men.”
13 And Lot said, Behold now, I have two daughters which have not known man; let me, I pray you, plead with my brethren that I may not bring them out unto you; and ye shall not do unto them as seemeth good in your eyes;
14 For God will not justify his servant in this thing; wherefore, let me plead with my brethren, this once only, that unto these men ye do nothing, that they may have peace in my house; for therefore came they under the shadow of my roof.
15 And they were angry with Lot and came near to break the door, but the angels of God, which were holy men, put forth their hand and pulled Lot into the house unto them, and shut the door.
19:11. blindness. Sarna translates this as due to a “blinding light,” not to the usual kind of sightlessness. Compare 2 Kings 6:18.
Genesis 19:12–29. The Destruction of Sodom
19:15. And when the morning arose, then the angels hastened Lot. Genesis scholar Ronald S. Hendel describes the scene, saying,
Lot is ineffectual and rather comic as he fails to convince his prospective sons-in-law to flee (v. 14). He hesitates to leave himself, so that the angels seize him and his family and drag them out of the city (v. 16). He also resists the angels’ instructions to flee to the hills and pleads for a closer refuge, the little city of Zoar (which means “little,” vv. 20, 22). Though Lot is a buffoon, his wife is even worse off, for she cannot resist a peek at the cities’ destruction in spite of the angels’ command not to look back. For this tragic flaw, she becomes a part of the landscape of the Dead Sea region, a pillar of salt.
André Chouraqui reads Lot’s request to go to Zoar differently than Hendel. He sees Lot as preferring a home in a more “civilized” place than in the appointed mountain retreat:
Lot is panic-stricken as he considers the austere solitude of the desert mountains near Sodom. In living the easy life, he’s gone soft and has lost the qualities of a true Hebrew.
19:24. Then the Lord rained upon Sodom and upon Gomorrah brimstone and fire from the Lord out of heaven. The locations of the five cities of the plain that were destroyed have proven impossible to identify with any certainty. A new phase of excavation began in 2005 at an archaeological site in Jordan called Tall el-Hammam. The excavators have suggested the possible identification of the site with the biblical Sodom and found evidence that the city was destroyed cataclysmically by an airburst. However, outside researchers have raised legitimate questions about some aspects of these conclusions.
The Birth of Moab and Ammon (19:30–38)
19:30. Lot went up out of Zoar, and dwelt in the mountain. Lot, out of fear, changed his mind about living in Zoar and retreated to the mountain as the angels had originally instructed.
19:32. Come, let us make our father drink wine, and we will lie with him. Fearing they would have children no other way, Lot’s daughters planned to conceive by their father.
19:37–38. and the firstborn bare a son, . . . Moab. . . . And the younger, she also bare a son . . . Ben-ammi. These sons are the traditional ancestors of the people of Moab and Ammon.
Nahum Sarna finds it “difficult to understand the point of this episode since neither people plays any role in the patriarchal narrative.” For several reasons, he rejected the common argument that the story was created to connect hated rival peoples to a shameful story of origin. Though there is a “law prohibiting Israelite intermarriage with them,” the law “is conditioned on Israel’s wilderness experience and is not based on the incestuous origin of these people. Indeed, their right to live peaceably in their respective homelands is acknowledged as God-given in Deuteronomy 2:9, 19. It should also be remembered that King David is descended from a Moabite woman, a fact clearly attested in Ruth 4:17–22.”
Genesis 20:1–18. Sarah and Abimelech
Nahum Sarna summarizes the situation as the chapter opens, saying,
Following the destruction of Sodom and Gomorrah, Abraham resumes his wanderings. Once again Sarah is taken away by force, this time to the harem of Abimelech, king of Gerar, who has been misled into believing that she is the patriarch’s sister.
Abraham was a foreigner, unprotected and subject to the same kind of maltreatment that readers just witnessed in Sodom. Forewarned by his previous experience with Sarah in Egypt, “Abraham now takes the initiative in passing off Sarah as his sister. He does not ask her for permission to do so.”
The story here seems to be another lesson in contrasts: Lot, the half-hearted Hebrew vs. Abimelech, the God-fearing pagan. Then, the morally and socially bankrupt Sodomites vs. Abimelech, the blameless monarch. Once again, the righteous Abraham played the role of a peace-seeking intercessor.
20:3–8. God came to Abimelech in a dream by night. God did not condemn Abimelech for his having taken Sarah but warned him that she was another man’s wife. Abimelech replied by telling God that he had done so innocently, having been misled by Abraham. Note that the king relied on the same argument for God’s justice that Abraham used in defense of the righteous of Sodom: “Lord, wilt thou slay also a righteous nation?” (The idea being that if the king died, the nation, who are dependent on the king for their welfare, would also suffer.)
God acknowledged the king’s integrity and promised that if Abimelech restored Sarah to Abraham, he would be blessed through Abraham’s prayers on his behalf. Significantly, in verse 7, Abraham was called a “prophet” (navi’)—the first time this word is used in the Bible.
In the last two verses of the story, we learn that Abimelech and his wives were barren throughout the episode, but began to “bare children” again after “Abraham prayed unto God” on their behalf.