After Isaac was offered, he was returned in resurrection for the fulfillment of God's eternal purpose (vv. 4, 12-13, 16, 18). After being returned in resurrection, Isaac was another person. He was no longer the natural Isaac, but the resurrected Isaac. This is very encouraging. After we have offered to God what we have received of Him, He will then return it to us in resurrection. Every gift, spiritual blessing, work, and success we have received of God must undergo the test of death. Eventually, it will come back to us in resurrection. The Lord Jesus said, "Truly, truly, I say to you, unless a grain of wheat falls into the ground and dies, it abides alone; but if it dies, it bears much fruit" (John 12:24). Suppose God gives you a certain natural gift. That is one grain of wheat. If you keep this natural gift, never offering it to God, it will remain as one grain. But if you offer it back to God, after it has passed through death, it will be returned to you in resurrection and become a blessing. It does not depend on what we can do or intend to do for God. It all depends on our growing up to be offered to God as a burnt offering and then being raised up from the dead to be a resurrected gift. It is not a matter of being useful to God but of being under His blessing. God's blessing always comes in resurrection. For one grain to be multiplied into a hundred grains is God's blessing. If you offer your one grain to God and allow Him to put it into death, it will be returned to you in resurrection. Then you will see multiplication and great blessing. This is God's way.
In Genesis 22 we see Abraham's obedience by faith. When I read this chapter as a young man, I could not understand how Abraham as a human being and a father could have been so bold. When God asked him to offer to Him his beloved son Isaac, he did it immediately. In this chapter there is no mention of Abraham's wife. According to the record here, we are not told that Abraham talked with his wife about offering Isaac. We are only shown that he responded quickly and boldly to God's command, rising up early in the morning and going to the place of which God had spoken.
In the Old Testament we cannot see why Abraham obeyed God so quickly and boldly. But in the New Testament we see that Abraham believed in the resurrecting God (Heb. 11:17-19; James 2:21-22). He had the faith which counted on God to raise up the very Isaac whom he was about to slay. He had received the firm and even confirmed promise that God's covenant would be established with Isaac and that he would become a great nation (17:19-21). If Abraham had offered Isaac on the altar, slaying him and burning him as an offering to God, and God did not raise him from the dead, then God's word would have been in vain. Abraham's faith was based upon God's confirmed promise. Abraham could have said, "If God wants Isaac, I will just slay him. God will raise him up for the fulfillment of His promise."
Romans 4:17, speaking of Abraham, says that the God in whom he believed is the One who "gives life to the dead and calls the things not being as being." Here we see that Abraham believed in God for two things: for giving life to the dead and for calling things not being as being. The birth of Isaac was related to God's calling things not being as being, and his being returned was related to God's giving life to the dead. Because Abraham had such faith, he obeyed God's commandment immediately. Hebrews 11:17-19 says that when Abraham was tried, he offered up Isaac by faith, "counting that God was able to raise him even from among the dead, from whence he also received him back in a figure."