All was not well in Abraham's household. Ishmael was a potential rival to Isaac's inheritance. This section records another crisis in the story of Abraham's heir.
Normally the son of a concubine became the heir of his mother but not of his father (cf. Judg. 9:1-3). Now that Abraham had a son by his wife, Sarah did not want Ishmael to share Isaac's inheritance. The Hebrew word translated "mocking"(v. 9) comes from the same root as Isaac's name and means "laughing."However this participle is in the intensive form indicating that Ishmael was not simply laughing but ridiculing Isaac (cf. Gal. 4:29). Abraham understandably felt distressed by this situation since he loved Ishmael as well as Isaac (cf. 17:18). God appeared to him again (the seventh revelation) to assure Abraham that Sarah's desire was in harmony with His will (cf. 17:19-21). He encouraged Abraham to divorce Hagar.
"But how could God ask Abraham to do evil if divorce is always a sin? The answer must be that divorce in this case is either not a sin or else is the lesser of two evils."560
"The key to Sarah's demand lies in a clause in the laws of Lipit-Ishtar where it is stipulated that the father may grant freedom to the slave woman and the children she has borne him, in which case they forfeit their share of the paternal property."561
The focus of this revelation is a clarification of God's purposes for each of the two sons. God would bless Abraham through Ishmael as well as through Isaac.
"As Cain suffered both banishment from the divine and protection by the divine, so Ishmael is both loser and winner, cut off from what should be his but promised a significant lineage."562
The concluding description of Ishmael's experiences (vv. 14-21) provides information essential to understanding and appreciating later references to him and his descendants in the text. Ishmael became the father of 12 sons (25:13-16) as Jacob did. From his sons came the Arab nations that have ever since been the chief antagonists of the Israelites.563Hagar chose a wife for her son from her homeland, Egypt.
"In this respect she does not display the wisdom used by Abraham in choosing, as he did, a god-fearing wife for his son."564
God not only makes promises but also provision. His provision of what He has promised results in great joy and should lead to separation from whatever might hinder His program of blessing.565
