He had intervened for them before, having personally rescued them from Chedorlaomer’s furious assault. But this time was different. The people of Sodom were in danger of heaven’s assault, and Abraham’s nephew lived among them. Thus began the Bible’s first intercessory prayer (Gen 18:23ff.), which contains helpful principles for us still.
Notice first that God’s activity directs our prayers. Abraham began his intercession directed by knowledge of the Lord’s plans. The Lord said, “Because the cry of Sodom and Gomorrah is great, and because their sin is very grievous; I will go down now …” (vv20-21). It was then that Abraham “drew near” (v23) and began to plead with the Lord to spare the city for the sake of any righteous within it. But he would not have prayed at all had the Lord not moved him first to do so. It is a blessing that God still moves His people to intercede for others. As we are naturally selfish and self-centered, would we ever think to pray for others if not for the fact that “God hath sent forth the Spirit of his Son into your hearts, crying, Abba, Father” (Gal 4:6)?
The second prayer principle here is that God’s righteousness anchors our prayers. Abraham knew there was at least one righteous person (Lot) within the city, which prompted his question, “Wilt thou also destroy the righteous with the wicked?” (v23). Such a prospect was unthinkable, provoking his bigger question, “Shall not the Judge of all the earth do right?” (v25). Abraham dropped his anchor here, and so can we. Assuming he was dealing with a righteous God, Abraham began to intercede accordingly. When we bring our prayers to the Lord, we can always trust Him to do what is right, even if things don’t make sense at the time. Although “clouds and darkness are round about him: righteousness and judgment [justice] are the habitation of his throne” (Psa 97:2).
Third, consider that God’s mercy motivates our prayers. God had been merciful to Abraham and Sarah, who both had their share of stumbles since called by the Lord. Abraham began to wonder how merciful God would be to the people of Sodom. Would He spare the city if 50 righteous lived there? What about 45, 40, 30, 20, 10? We know that God is full of mercy, for it was “according to his mercy he saved us” (Titus 3:5). And so we are motivated to pray for our children, neighbors, friends and co-workers who desperately need Christ, aware that God is “rich in mercy” (Eph 2:4).
Finally, Abraham’s intercession indicates how God’s greatness regulates our prayers. At least, it should. Abraham’s boldness was matched by his humility, recognizing that he was “but dust and ashes” (v27) and that the One he was addressing is Adonai (master, ruler), a title he uses four times (vv27-32). He proceeded cautiously and reverently in his intercession. “Name it and claim it” prayers from we who are “but dust and ashes” are an affront to our Sovereign Lord. Although we can now call God our Father and are invited to boldly approach the throne of grace, we must remember that we approach the throne; the Lord sits upon it. “Great is the LORD … his greatness is unsearchable” (Psa 145:3).
 Bible quotations in this article are from the KJV.