Genesis 17:15-19

Isaac’s Birth Promised

15And God said to Abraham, “As for Sarai your wife, you shall not call her name Sarai, but Sarah
 Sarai and  Sarah mean princess
shall be her name.
16I will bless her, and moreover, I will bgive
Hebrew have given
you a son by her. I will bless her, and dshe shall become nations; kings of peoples shall come from her.”
17Then Abraham efell on his face fand laughed and said to himself, “Shall a child be born to a man who is a hundred years old? Shall Sarah, who is ninety years old, bear a child?” 18And Abraham said to God, “Oh that Ishmael might live before you!” 19God said, “No, but gSarah your wife shall bear you a son, and you shall call his name hIsaac.
 Isaac means he laughs
I will establish my covenant with him as an everlasting covenant for his offspring after him.

Genesis 18:10-14

10The Lord said, “I will surely return to you jabout this time next year, and kSarah your wife shall have a son.” And Sarah was listening at the tent door behind him. 11Now lAbraham and Sarah were old, advanced in years. The way of women had ceased to be with Sarah. 12 mSo Sarah laughed to herself, saying, nAfter I am worn out, and omy lord is old, shall I have pleasure?” 13The Lord said to Abraham, “Why did Sarah laugh and say, ‘Shall I indeed bear a child, now that I am old?’ 14 pIs anything too hard
Or wonderful
for the Lord? rAt the appointed time I will return to you, about this time next year, and Sarah shall have a son.”

Genesis 21:1-2

The Birth of Isaac

1The Lord svisited Sarah as he had said, and the Lord did to Sarah tas he had promised. 2And Sarah uconceived and bore Abraham a son in his old age vat the time of which God had spoken to him.

Romans 4:18-21

18In hope he believed against hope, that he should become the father of many nations, as he had been told, wSo shall your offspring be.” 19He did not weaken in faith when he considered his own body, which was xas good as dead ( ysince he was about a hundred years old), or when he considered zthe barrenness
Greek deadness
of Sarah’s womb.
20No unbelief made him waver concerning the promise of God, but he grew strong in his faith as he gave glory to God, 21fully convinced that abGod was able to do what he had promised.

Romans 10:8

8But what does it say? ac“The word is near you, in your mouth and in your heart” (that is, the word of faith that we proclaim);

Hebrews 11:11

11By faith adSarah herself received power to conceive, even when she was past the age, since she considered aehim faithful who had promised.
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