God was testing Abraham to see if he really believed and trusted God. Then, because Abraham did trust God, God stepped in and provided an animal to be sacrificed instead. This was a foreshadow of the sacrificial system to come (the Law), and a foreshadowing of the true sacrificial Lamb, (Jesus) that was provided to make salvation possible for all who believe. Jesus was the final sacrifice as He fullfilled the requirements of the Law. For the law said that the wages (cost) of sin is death. Jesus paid the full cost of that debt. Like Abraham all God asks of us is to trust and believe in His finished work on the cross and to embrace the New Covenant of Grace that He offers to all humanity now. 😇