After being dealt with by God for so many years, what kind of person did Abraham become? He became a person who had no trust in himself. Then God said to him, "As for Sarai thy wife, thou shalt not call her name Sarai, but Sarah shall her name be. And I will bless her, and give thee a son also of her" (Gen. 17:15-16). God had promised Abraham earlier that "he that shall come forth out of thine own bowels shall be thine heir." At that time Abraham had believed. After more than ten years, God came again and told him that he would have a son through his wife Sarah. What did Abraham do? He was not as bold as before. He did not have the faith that he had before. When he heard God's promise, he "fell upon his face, and laughed, and said in his heart, Shall a child be born unto him that is a hundred years old? and shall Sarah, that is ninety years old, bear?" And he said to God, "O that Ishmael might live before thee!" (vv. 17-18). This means that he had given up hope entirely in himself. He considered his own body as being already dead and Sarah's womb as being deadened. He could not recall how he had believed at the beginning. He might have said, "Perhaps I was young and could believe then. But now, how can I believe anymore?" In man's eyes Abraham had backslidden all the way. He had backslidden so much that even his faith was seemingly gone.
Actually, the little faith that Abraham had years ago was a faith that was mixed up with the flesh. It was a faith which begot Ishmael with the flesh. For thirteen years God put Abraham aside and brought him to his end so that he would be purified. It seemed as if Abraham had failed. Yet God was still working on him. We have to remember that God's work may not be with us when we are victorious, and God's work may not be altogether absent from us when we fail. We should commit ourselves to the hand of the ever-living Lord. As long as He has called us and has started His work in us, He will never give up. Even when we are weak and failing, He still carries on His work, and He is still leading us on step by step.
When God repeated to Abraham that his wife Sarah would bring forth a son, he fell upon his face and laughed. Was he laughing at God? No, he was really laughing at himself. It was too impossible of a situation for him. Yet in the midst of such a situation, he believed in God. It is strange that in easy situations, it is hard to believe in God, while in hard situations, it is easy to believe in God. Easy situations do not help a person believe in God. When a man reaches a desperate situation, he truly believes in God. Hence, God always guides us in two ways: He causes us to trust in Him by bringing us to the end in our environment and by bringing our flesh to its end. The lesson from the environment is outward, while the lesson from circumcision is inward. For Sarah's womb to be deadened was an end in the environment; this was something outward. For Abraham to be circumcised was for his flesh to be brought to its end; this was something inward. We must be brought to our end before we can believe in God. If our flesh is dealt with, we will believe in God whether the environment is smooth or difficult.
God does not want a mixed faith, but a pure faith. We should not believe only when things look bright and we have confidence in ourselves. We should believe simply because God has spoken. Abraham could not believe in this way thirteen years previously. But now he was brought to the point where he considered his body as being already dead and his wife's womb as being deadened. The faith which he now had was a pure faith; it was one that believed in God alone. His previous faith was based on God and on himself. His faith now was based on God alone because all his strength was gone, and there was nothing left in him; everything was finished. Abraham's laugh confirms this: To him everything in him was finished. Yet God said to him, "Sarah thy wife shall bear thee a son indeed; and thou shalt call his name Isaac" (17:19).
We should take note of this fact: God wanted Abraham to beget Isaac, not Ishmael! God will never accept any replacement of His work. After He waited for thirteen years, He still wanted Abraham to beget Isaac. Ishmael can never satisfy God's heart!
Genesis 17:23-24 says, "And Abraham took Ishmael his son, and all that were born in his house, and all that were bought with his money, every male among the men of Abraham's house; and circumcised the flesh of their foreskin in the selfsame day, as God had said unto him. And Abraham was ninety years old and nine, when he was circumcised in the flesh of his foreskin." Abraham's circumcision was his acknowledgment that he was through, that his flesh absolutely could not make it. As far as his own condition was concerned, he could not even believe in God's promise. But just when he could not believe anymore, the real faith came in! When he could believe no longer and when he could do nothing anymore, he truly trusted in God. It seemed as if he believed and, at the same time, was unable to believe. There was only a flicker of faith in him. Yet this flicker of faith was the pure faith. Abraham's condition at this time is described in Romans 4:19-20: "And not weakening in his faith, he considered his own body as already dead, being about a hundred years old, as well as the deadening of Sarah's womb; but with regard to the promise of God, he did not doubt in unbelief, but was empowered by faith, giving glory to God."