Waiting for the Promised Seed (Gen 16-21)
Is it too fanciful to see the timing of the covenant as being a preparation for the most taxing experience of Abrahams life so far? The ups and downs of his family life would last for many years. There was the blind alley of using Hagar as a kind of surrogate mother to help God out of a supposed difficulty by providing a son who could be called Sarahs son. This was not Gods way. But Sarahs barrenness was not the only problem in those long years: as time went by it became clear that Abrahams ability to beget a son was at least open to question. Abrahams walk with God required more than decisive action, when a rush of adrenalin might contribute to his actions: he had to learn to continue to trust God when years passed by and the prospect of the birth of the promised seed must have seemed ever more remote. Sarahs solution to the dilemma by gaining a son through Hagar is easy to understand. Abraham loved the son born in this way, Ishmael. But he had to learn that Ishmaels birth was not a fulfilment of the promise: he was not the son of promise.
This left them with a problem which became more and more acute as the years passed by. Barren wives are a commonplace feature of Bible stories. There came a time when Sarah, the barren wife, reached another milestone "it ceased to be with Sarah after the manner of women" (18.11) - she had passed the menopause. Abraham was also, humanly speaking, past the stage when he could beget a son. The situation could only be described as impossible. At this point the Lord said to Abraham, "Is anything too hard for the Lord?" (18.14). We remember that this reassurance was applied also to Zacharias and Elizabeth in Luke 1.37, where the words are given in the Septuagint translation of Genesis 18.14: "For with God nothing shall be impossible". Paul in Romans 4.18 states the situation succinctly, when he writes that Abraham "against hope believed in hope". The sense is that, when evidence and human reason would have led him not to believe, he believed and therefore expected God to be as good as His word.
At the point where human reason and resources held out no hope, God intervened. God, who is the source of all life, intervened when Abrahams body was "as good as dead" (Rom 4.19, RV), and Sarahs womb was dead. Knowledge of the living God, Creator and source of all life, equips us to deal with situations beyond human resources. It would arm Abraham for the supreme test of his faith.
Abrahams Faith: the ultimate test (Gen 22)
Ishmaels birth had been a false dawn. With difficulty Abraham had been able to disown Hagar and Ishmael. He had to do this, for the inheritance was for the son of promise. He had to drive out Ishmael and Hagar after Ishmael offended Sarah by his treatment of Isaac. So Abraham and Sarah were left with one son, the seed promised, born through the power of the living God, the God of the impossible.
Then God tested Abraham. What was at issue was his relationship with God. Was God to be implicitly trusted and obeyed, or not? Could Abraham trust God without being able to explain the demands that God would make? The command came abruptly: "Take now thy son, thine only son Isaac, whom thou lovest...and offer him...for a burnt offering" (Gen 22.2). There was no immediate circumstance to support Abrahams faith; his support was the accumulated experience of the faithfulness of God, the living God, the God of the impossible.
Abrahams response was prompt and wholehearted: he "rose up early in the morning" - a sure sign of his willingness to make a thorough job of what God demanded. He made due preparation of the materials to be used. He had three days of travelling along with Isaac to give him time to think about the strange demand.
The deep significance of the place is indicated by the expression, "lifted up his eyes, and saw". Abraham had already come to a conclusion in his thoughts about Gods demand. He told the young men to wait where they were while he and the lad went yonder and worshipped and (note well) would "come again" to them. We cannot escape the conclusion expressed in Hebrews 11.19: "accounting that God was able to raise him up, even from the dead". The God who had enabled Abraham, a man "as good as dead", to become a father, and Sarah, a woman whose womb was "dead", to produce a son, could raise a young man from the dead.
Abraham was able to refuse to consider two conclusions. He knew that God had not made a mistake in demanding the sacrifice. He also knew that God had not decided to break His promise of a seed through Isaac. God, he knew, does not make mistakes and does not break promises. On this occasion God did not intervene until the very last moment, when the sacrificial knife was poised above the victim. He knew Abraham had advanced so far in his faith as to need no props to lean on in advance of the critical moment of testing. It is not by chance that the word "worship" is prominent in v.2. Our ability to obey Gods difficult demands comes from an appreciation of His greatness and goodness. He has our best interests at heart.
Conclusion
The journey of faith which took Abraham out of Ur, and led him through tests and trials, brought him to a rich appreciation of God. He "died in a good old age, an old man, and full of years" (Gen 25.8). His is a story of a life enriched by the fact that he walked before God (Gen 17.1) and proved Him to be El Shaddai, the All-Sufficient One.
Concluded.