Abram was seventy-five years old when the LORD told him to leave the city of Haran. He obeyed and left with his wife Sarai, his nephew Lot, and all the possessions and slaves they had gotten while in Haran. When they came to the land of Canaan,
Abraham bowed with his face to the ground and thought, "I am almost a hundred years old. How can I become a father? And Sarah is ninety. How can she have a child?" So he started laughing.
Abraham let himself be circumcised to show that he had been accepted because of his faith even before he was circumcised. This makes Abraham the father of all who are acceptable to God because of their faith, even though they are not circumcised.