“But God said to Abraham, “Do not be distressed about the boy and your maidservant. Listen to everything that Sarah tells you, for through Isaac your offspring will be reckoned.”

Genesis 21:12

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Go deeper on this verse (5)

Why was Abraham distressed?
Sarah demanded that Hagar and her son be sent away, and Abraham was distressed, because the boy was his son too. God told him to listen to Sarah and promised to make a nation of the slave woman's son as well (Genesis 21:13).
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Ishmael's Unspoken Name and the Well Hagar Could Not See (Genesis 21)
Connection with Abraham offering Isaac
Years later God commanded Abraham to offer Isaac (Genesis 22:2), and this older promise about the same boy seemed to stand against it. Hebrews explains how Abraham held both: "Abraham reasoned that God could raise the dead" (Hebrews 11:19).
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Connection with Abraham's will
Abraham took this promise to heart. Before he died he left everything he owned to Isaac and sent the sons of his concubines away east with gifts (Genesis 25:5), so nobody would dispute Isaac's place at his graveside.
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Connection with "obey my voice"
In Genesis 27:13 Rebekah told Jacob, "Just obey my voice and go get them for me." The phrase can point the right way: here God Himself told Abraham, "Listen to everything that Sarah tells you." Each time, the question is whether the voice being obeyed carries what God said.
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