There is no idea or hint that there was any doubt that God would not provide a sacrifice—a substitute sacrifice. He knew that God had said, "and make him a burnt offering," but he also knew God.
At this point, he had maybe 50 years or so with God. God called him when he was 75. Isaac was born when he was about 100, and tradition says that Isaac was 33 when this occurred. It is hard to say. If that is the case, he had more than 50 years (about 58) of experience with God.
He knew God. He was God's friend. He knew that this was not something that God would go through with. Abraham knew the eternal, unchanging, holy, righteous character of God. He knew that God would not have him go through this horrid human sacrifice.
So, what did he have? We often look at this in terms of faith. It is a wonderful example of faith, but it is also a great example of hope, because the faith was the foundation for his hope.
You see, there was a promise that God had given him years before, and He said, "Your seed will inherit this land. In you the whole world will be blessed."
So Abraham put two and two together. "God has promised. I have one son who He said is the one that the seed would come through." He knew God. He bargained with God with the events in Sodom and Gomorrah. He got God down to 10, and God did what He said He would do.
And he had his own experiences with the birth of Isaac. He had gone to all those lengths to circumvent God, but God brought along Isaac exactly as He promised. So, Abraham had several examples to look back upon to see what God's character was, and then applied what he learned to this situation.
God tells him, "sacrifice your son," and Abraham says, "This all adds up." That is exactly what the book of Hebrews says about him—that it all added up.
What added up? God was not going to have him kill Isaac! He had hope that he would see his son live to be an old man (a father). So, he acted. He said, "Let's go. Let's do what God says, and God will provide."
He had hope. "Well, if God will have me kill him that will not stop God's promise. He could raise him from the dead. Isaac will live." There was hope for life. And so, he went through it.
The word “lad,” here, means “a boy,” or better yet, “a young man.” So how old was Isaac at this time? Now the word translated young men is the same, although it is plural, is the same word as translated “lad.” The Jewish historian Josephus gives Isaac's age at this time as 25. Rabbinical tradition has it at 36. Then I read several other commentators who put it at 33. Personally, I feel he was 33 at this time. He was not a little boy. His life and every step of this episode parallels that of Christ, so I do believe 33 was his age.
And Abraham says, “We will come back to you.” We! We will come back to the young men waiting there by the donkey. Was he lying to these young men? Abraham was the father of the faithful. I do not think he was lying to them. He would have thought this thing through.
It says of Abraham in Hebrews 11:19 that he had added up the evidence, and he knew that the promises required Isaac. He did not know for sure that God was going to resurrect him. But he had the faith; he thought it through. If you put yourself in this position, I do not care if you do know with ironclad certainty that God is going to resurrect your son, Abraham still had to kill his son! How many of us would have that kind of faith?
If we take those verses at face value, he made every preparation to sacrifice his son, and yet he also expected to bring him back. But how, if he was sacrificed as God said? The answer is supplied in Hebrews 11, where it shows that Abraham’s resolution was such that Isaac was as good as dead. But Abraham received him back as it says, in a figure, that is, by means of a resurrection.
Here we are on the third day and in the story Abraham's faith is noticeably coming to the fore. Any wrestling that he had done with God had slipped into the background even though, without a doubt, a great deal of emotion remained, his resolve was set. "The lad and I will come back".
