Genesis 21:10-12

21:10 So she said to Abraham, “Banish ¹  that slave woman and her son, for the son of that slave woman will not be an heir along with my son Isaac!”

21:11 Sarah’s demand displeased Abraham greatly because Ishmael was his son. ²  21:12 But God said to Abraham, “Do not be upset ³  about the boy or your slave wife. Do ⁴  all that Sarah is telling ⁵  you because through Isaac your descendants will be counted. ⁶ 

[21:10]  ¹ tn Heb “drive out.” The language may seem severe, but Sarah’s maternal instincts sensed a real danger in that Ishmael was not treating Isaac with the proper respect.

[21:11]  ² tn Heb “and the word was very wrong in the eyes of Abraham on account of his son.” The verb רָעַע (ra’a’) often refers to what is morally or ethically “evil.” It usage here suggests that Abraham thought Sarah’s demand was ethically (and perhaps legally) wrong.

[21:12]  ³ tn Heb “Let it not be evil in your eyes.”

[21:12]  ⁴ tn Heb “listen to her voice.” The idiomatic expression means “obey; comply.” Here her advice, though harsh, is necessary and conforms to the will of God. Later (see Gen 25), when Abraham has other sons, he sends them all away as well.

[21:12]  ⁵ tn The imperfect verbal form here draws attention to an action that is underway.

[21:12]  ⁶ tn Or perhaps “will be named”; Heb “for in Isaac offspring will be called to you.” The exact meaning of the statement is not clear, but it does indicate that God’s covenantal promises to Abraham will be realized through Isaac, not Ishmael.