What does Genesis 20:7 mean?God has appeared to Abimelech, king of Gerar, in a nighttime dream. God has stated flatly that Abimelech will die from his current illness for taking Sarah as his wife, since she is a married woman (Genesis 20:3; 20:17). When Abimelech protested that he did not know this, God agreed that Abimelech acted with integrity and had not yet touched Sarah, albeit because of God's own intervention (Genesis 20:6).
Now God gives Abimelech a choice about whether he will live or not. He is to return Sarah to Abraham. When he does so, Abraham will pray, and Abimelech and his household will live. Otherwise, they will all die.
This is the first use of the Hebrew word for prophet, nabiy', in the Old Testament. God considered Abraham to be a prophet, one who speaks for God and to God on behalf of others. Abraham has already approached God on behalf of Lot and the people of Sodom in Genesis 18.
Apparently, this is the end of God's conversation with Abimelech in a dream. When morning comes, Abimelech will quickly act on what the Lord has said to him.