God’s Faithfulness to Sarah and Abraham
Genesis 17:15–22 (NASB95)
15Then God said to Abraham, “As for Sarai your wife, you shall not call her name Sarai, but Sarah shall be her name. 16“I will bless her, and indeed I will give you a son by her. Then I will bless her, and she shall be a mother of nations; kings of peoples will come from her.” 17Then Abraham fell on his face and laughed, and said in his heart, “Will a child be born to a man one hundred years old? And will Sarah, who is ninety years old, bear a child?” 18And Abraham said to God, “Oh that Ishmael might live before You!” 19But God said, “No, but Sarah your wife will bear you a son, and you shall call his name Isaac; and I will establish My covenant with him for an everlasting covenant for his descendants after him. 20“As for Ishmael, I have heard you; behold, I will bless him, and will make him fruitful and will multiply him exceedingly. He shall become the father of twelve princes, and I will make him a great nation. 21“But My covenant I will establish with Isaac, whom Sarah will bear to you at this season next year.” 22When He finished talking with him, God went up from Abraham.
God spoke directly to Abraham and declared that his wife’s name would no longer be Sarai but Sarah, meaning “princess.” This new name marked her as the mother of nations and kings. God included Sarah in the covenant, giving her a place of honor and promise. God said He would bless her and she would bear a son. This was not a vague hope. God gave a clear and specific promise. Sarah, though far beyond childbearing years, would become the mother of Isaac. God’s word cut through every human limitation.
Just as God used Adam and Eve to begin a new creation with the human family, God now has chosen Abraham and Sarah to bring forth a new nation that will be Israel.
Abraham responded with laughter. He could not imagine a child being born to a man one hundred years old and a woman ninety years old. His laughter showed both amazement and doubt. Abraham asked God to let Ishmael live under His blessing. Abraham cared for his first son and wanted God’s favor for him. God answered with certainty. He said Sarah would bear Isaac, and the everlasting covenant would be with Isaac. God did not reject Ishmael. He promised to bless him and make him a great nation with twelve rulers. Still, the covenant would pass through Isaac alone. God set a clear timeline. Sarah would have a son at the same time next year. God’s promise was sure and unchanging.
The church today must remember that God’s promises do not depend on human strength or understanding. God is faithful even when we doubt. He includes the unlikely and fulfills His word in His time. The church should trust God’s promises, bring doubts honestly to Him, and rest in His faithfulness. God’s covenant with Abraham and Sarah points to the greater promise fulfilled in Jesus, who brings all who believe into the family of God. The church can live with confidence, knowing God can accomplish more than we can ask or imagine.