Genesis 18:10

10The Lord said, “I will surely return to you aabout this time next year, and bSarah your wife shall have a son.” And Sarah was listening at the tent door behind him.

Genesis 21:1-2

The Birth of Isaac

1The Lord cvisited Sarah as he had said, and the Lord did to Sarah das he had promised. 2And Sarah econceived and bore Abraham a son in his old age fat the time of which God had spoken to him.

Hebrews 11:11-12

11By faith gSarah herself received power to conceive, even when she was past the age, since she considered hhim faithful who had promised. 12Therefore from one man, and ihim as good as dead, were born descendants jas many as the stars of heaven and as many as the innumerable grains of sand by the seashore.

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