How strong is the snare of the things that are seen, and how necessary for God to keep us in the things that are unseen! If Peter is to walk on the water, he must walk; if he is going to swim, he must swim, but he cannot do both. If the bird is going to fly it must keep away from the fences and the trees, and trust to its buoyant wings. But if it tries to keep within easy reach of the ground, it will make poor work of flying.
God had to bring Abraham to the end of his own strength, and to let him see that in his own body he could do nothing. He had to consider his own body as good as dead, and then take God for the whole work, and when he looked away from himself, and trusted God alone, then He became fully persuaded that what He had promised, He was able also to perform.
This is what God is teaching us, and He has to keep away encouraging results until we learn to trust without them, and then He loves to make His word real in fact as well as faith.
Let us look only to Him to-day to do all things as He shall choose and in the way He shall choose.