TMK: My suggestion is that you begin searching out all scriptures dealing with God's covenant with Abraham, both New and Old Testament. Three from Hebrews have already been posted, and the poster is right about them. The point is not human sacrifice. There is so much more going on here.
God has always dealt with man through covenant. He made covenant with Abraham and promised Abraham that in his seed would all nations of the earth be blessed. Paul makes a very big distinction in Galatians that God said seed singular and not seeds plural, meaning a particular descendant of his son Isaac (in Isaac shall thy seed by called) was to bless all nations.
The writer of Hebrews shows us that Abraham accounted that God would raise his son from the dead, from which he had already received him in a figure.
If God is in covenant with Abraham, and if Abraham offers his only begotten son (Look that on up if you will. Abraham had two sons, but God calls Isaac his only begotten. Very interesting, but born out in Romans 7 by Paul.) If Abraham offers his only begotten, then God is allowed to (perhaps obligated to) offer His only begotten Son as well. It is part of covenant. This is why we, being born again believers, are no longer under the covenant of law, but are now under the same covenant as Abraham. A covenant of faith.
So I believe that Abraham was actually shown by God the end game of His sacrifice. He, in my opinion , showed Abraham the sacrifice of Christ. This is born out by Jesus words in John 8:56. Abraham rejoiced to see my day, and saw it, and was glad.
So Abraham goes boldly to offer his son, knowing that just like Jesus was going to be raised from the dead, his own son Isaac would have to be. Why, because God had already showed Abraham Jesus day in a figure. Amazing stuff, and sheds some really powerful light on the plan of salvation. Praise God that Abraham believed God and was obedient in offering his son.
My take. Blessings as you study this out.