Hebrews 11:11-12 (HCSB)
By faith even Sarah herself, when she was unable to have children, received power to conceive offspring, even though she was past the age, since she considered that the One who had promised was faithful. Therefore from one man—in fact, from one as good as dead—came offspring as numerous as the stars of heaven and as innumerable as the grains of sand by the seashore.

The exhibit on the faith of Abraham continues with his next act of faith: fathering Isaac.

From the moment He called him, God promised to multiply Abraham and to make him into a great nation (Genesis 12:1-3). This was perhaps a bit strange, since Abraham was seventy-five years old when God called him to leave behind his family and security in order to go to Canaan, and he was married to a sixty-five-year-old barren woman, Sarah.

Abraham believed God’s promise, but he could see no way for the promise to be fulfilled, since he had not yet learned that God could do miracles. It was this lack of understanding the led him and Sarah to take matters into their own hands, to try to fulfill God’s promise in their own power, leading to the whole issue with Hagar and Ishmael, which ultimately led to a lot of heartache and conflict that still continues today.

But the time came when Abraham was ninety-nine years old, and Sarah was eighty-nine, that God spoke definitively to Abraham, telling him that it would be Sarah who would become pregnant. His barren wife who was well past the age of childbearing would have a child by him (Genesis 18:10-15).

But the child who would be born would not be a virgin birth where God did all the work. He was to be the natural child of Abraham and Sarah. Abraham believed the promise. But his step of faith was to make love to his wife, so that God could do His part and make the union successful. Without that concrete action on his part, which the writer of Hebrews calls “faith”, all the “belief” in the world would not have resulted in the pregnancy, which in turn led to the beginning of God’s chosen people.

Father, this is an amazing point. Sarah’s statement in regard to Your promise, “After I have become shriveled up and my lord is old, will I have delight?” (Genesis 18:12), seems to show that they had stopped having sexual relations. But in response to Your promise, Abraham took the initiative to start again. And that step of faith was rewarded. Lord, what things have I given up on that You might call on me to restart with renewed vigor, so that You can show yourself powerful through them? Help me to hear You clearly today, so that I can take my own steps of faith. Amen.