Genesis 22:3-14 NIV
 Early the next morning Abraham got up and loaded his donkey. He took with him two of his servants and his son Isaac. When he had cut enough wood for the burnt offering, he set out for the place God had told him about.  On the third day Abraham looked up and saw the place in the distance.  He said to his servants, “Stay here with the donkey while I and the boy go over there. We will worship and then we will come back to you. ”  Abraham took the wood for the burnt offering and placed it on his son Isaac, and he himself carried the fire and the knife. As the two of them went on together,  Isaac spoke up and said to his father Abraham, “Father?” “Yes, my son?” Abraham replied. “The fire and wood are here,” Isaac said, “but where is the lamb for the burnt offering?”  Abraham answered, “God himself will provide the lamb for the burnt offering, my son.” And the two of them went on together.  When they reached the place God had told him about, Abraham built an altar there and arranged the wood on it. He bound his son Isaac and laid him on the altar, on top of the wood.  Then he reached out his hand and took the knife to slay his son.  But the angel of the Lord called out to him from heaven, “Abraham! Abraham!” “Here I am,” he replied.  “Do not lay a hand on the boy,” he said. “Do not do anything to him. Now I know that you fear God, because you have not withheld from me your son, your only son. ”  Abraham looked up and there in a thicket he saw a ram caught by its horns. He went over and took the ram and sacrificed it as a burnt offering instead of his son.  So Abraham called that place The Lord Will Provide. And to this day it is said, “On the mountain of the Lord it will be provided .”
Two things amaze me about Abraham's obedience to God here. The first is that his obedience was immediate, revealed by the little phrase: "Early the next morning....." (v. 3) Most of us would say that we really want to do what God asks, but often we put it obedience off until a more convenient time or we delay hoping that God might change His mind or forget about it altogether. We're a little like Augustine when it came to sexual purity. In his book 'Confessions', he says:
"As I prayed to God for the gift of chastity, I had even pleaded: 'Grant me chastity and self-control, but please not yet.' I was afraid that You might hear me immediately and heal me forthwith of the morbid lust which I was more anxious to satisfy than to snuff out."
At least he's honest! Abraham did the thing he least wanted to do without delay or procrastination.
Secondly, as well as immediate obedience, Abraham demonstrated continued obedience. Look at verse 4: "On the third day Abraham looked up and saw the place in the distance."
The journey to the appointed place of sacrifice took three days. Imagine 72 hours of travelling, every step thinking about what you would have to do when you arrived at your destination, every thought preoccupied with dread, every glance at Isaac reminding him what he was about to lose. It's one thing to start out on a journey of obedience. It's quite another to keep going when everything within you wants to turn around. Eugene Peterson describes the Christian life as "a long obedience in the same direction." In a world that craves the instant, new, novel, emotional and exciting, this isn't what we want to hear.
Abraham didn’t know the answers, but he trusted God all the same. No matter what the circumstances looked like and how close to death Isaac came, he had experienced enough of God to obey even when it hurt most. Somehow he just knew that God wouldn't fail, God couldn't fail him. He told his servants by faith in verse 5 that he was certain that after he and Isaac had gone up the mountain, “we will come back to you”. He also told Isaac in verse 8 that “God himself will provide the lamb for the burnt offering.” The writer to the Hebrews tells us that he even believed that if he killed his son Isaac, the Lord would raise him back to life. (11: 19)
He was right. God came through, stopping him at the last moment and providing a ram for the sacrifice.
Think about the imagery: There in the thicket was an innocent ram. It's head was surrounded by thorns and it was impaled on Mount Moriah, the mountain where Solomon would later build his Temple. It had a rocky outcrop which the Romans would later call Calvary. Isaac’s life was spared, but centuries later God's only son would be sacrificed on the same spot. We read in Roman's 8:32: “God did not spare his own Son, but gave him up for us all.". God put a monumentally hard demand on Abraham, but it was an expectation God was also prepared to fulfill. He followed through in allowing His sinless son to die, all so that we might receive the benefits and rewards from His death.