Isaac trusted his father much the same way that Abraham trusted God. God promised this child to Abraham and Sarah many years before, as they were passing through the plain of Moreh, when Canaanites were in the land.
And the LORD appeared unto Abram, and said, Unto thy seed will I give this land: and there builded he an altar unto the LORD, who appeared unto him. (Genesis 12:7 KJV)
Without a child to fulfill this promise, Abraham believed God and built an altar. In later years, Abraham laughed at God’s promise, even as God changed his name.
Then Abraham fell upon his face, and laughed, and said in his heart, Shall a child be born unto him that is an hundred years old? and shall Sarah, that is ninety years old, bear? (Genesis 17:17 KJV)
God had a plan, and a name for the child yet to be born.
But my covenant will I establish with Isaac, which Sarah shall bear unto thee at this set time in the next year. (Genesis 17:21 KJV)
Yet Sarah disbelieved, and laughed at God’s promise, too.
Therefore Sarah laughed within herself, saying, After I am waxed old shall I have pleasure, my lord being old also? (Genesis 18:12 KJV)
For those of us who believe the Bible to be God’s word, we find His answer full of promise:
Is any thing too hard for the LORD? At the time appointed I will return unto thee, according to the time of life, and Sarah shall have a son. (Genesis 18:14 KJV)
And, it was so. Now, in chapter 22, God has called upon Abraham to offer this son, this promise fulfilled child from God, and offer him as a sacrifice. It was being done by other religions in the area then. It could be said it is still done today, as young men are sacrificed to blow up others.
They spoke as they walked together to make the altar, and without foreknowledge, Abraham spoke across the ages.
And Isaac spake unto Abraham his father, and said, My father: and he said, Here am I, my son. And he said, Behold the fire and the wood: but where is the lamb for a burnt offering? And Abraham said, My son, God will provide himself a lamb for a burnt offering: so they went both of them together. (Genesis 22:7-8 KJV)
God will provide himself a lamb. And, He did just that. He announced it through the voice of one crying in the wilderness:
The next day John seeth Jesus coming unto him, and saith, Behold the Lamb of God, which taketh away the sin of the world. (John 1:29 KJV)
In case you didn’t hear it the first time,
And looking upon Jesus as he walked, he saith, Behold the Lamb of God! (John 1:36 KJV)
Promised, laughed at, revealed.
And now ye know what withholdeth that he might be revealed in his time. (2 Thessalonians 2:6 KJV)
Abraham and Isaac by Johann Heinrich Ferdinand Olivier 1817