Sacrifice of Isaac

Following passage is my favorite part from The Living God book which was sent by my Dad,

"Remember that patriarch Abraham and his wife Sarah had a son in their old age, Isaac, according to the promise which the Lord had made them. One can easily imagine Abraham's and Sarah's great joy at the birth of their first child, and the love with which they surrounded Isaac, who had been given to them by God as a reward for their faith, with the promise of a multitude of descendants. But God was going to test Abraham again, using this son Isaac. The Book of Genesis tells us the story (Gen 22:1-14):

[God] said, "Take now your son, your only son Isaac, whom you love and go to the land of Moriah, and offer him there as a burnt offering upon one of the mountains of which I shall tell you."

You must understand clearly: God orders Abraham to kill his beloved son and to offer him as sacrifice; and Abraham does not hesitate, just as he did not hesitate during the previous trials. He saddles a donkey, chops wood for the fire, and sets out, taking two servants and his son. After travelling for three days, Abraham sees the place which had been indicated to him in the distance and orders his servants to wait for him with the donkey. He puts the wood on Isaac's back, takes fire and a knife, and they move on together. Isaac's walking with the wood on his soulders up to the place of sacrifice reminds us of the Lord Jesus' carrying His Cross up to Golgotha.
The story continues. Isaac asks his father, "Behold the fire and the wood: but where is the lamb for a burnt offering?" And Abraham answers, "God will provide Himself the lamb for a burnt offering, my son." Upon reaching the place which had been indicated indicated, Abraham builds an altar, puts down the wood, and ties Isaac upon the altar. But at the moment he takes up the knife to destroy his son, the angel of the Lord calls to him and says, "Do not lay your hand on the lad or do anythingto him; for now I know that you fear God, seeing you have not withheld your son, your only son, from me." Then Abraham sees a ram caught by its horns in a bush and offers it as a sacrifice instead of his son. Abraham called this place, "The Lord provides."Then the angel of renews God's promise to Abraham: "I will indeed bless you, and I will multiply your descendants as the stars of heaven as the sands which is on the seashore. And your descendants shall possess the gate of their enemies, and by your descendants shall all the nations of the earth bless themselves, because you have obeyed my voice" (Gen 22:17).

The simplicity of this story is astonishing. It does not deal with Abraham's feelings, his anguish, or his fears. we are not told wheter the knife trembled in his hand. Abraham does not understand why this sacrifice is demanded of him, nevertheles, he obeys in a gesture of absolute faith. Isaac also shows total confidence in his father and does not rebel against him. The sacrifice of the heir of the promise, the instrument of all his hopes, which is demanded of Abraham, require a faith above all reasons, an absolute obedience and a total confidence in God. Abraham is convinced that, in spite of all appearances, God will keep His promise. Once again, we are clearly shown that the history of salvation is made up not only of God's decisions but also of man's will, when a man knows that his hope is rooted only in God: "Thy will be done."

The Living God: A chatechism volume I - pages 147-149.