Why didn't Abraham have to kill Isaac in Genesis 22?
Because the Sovereign God provided the sacrifice instead. In Genesis 22 a ram was caught in the thicket, and Abraham recognized God's provision at verse 14, naming the place Jehovah Jireh, which means "I am your provider" in Hebrew. Thus Isaac was spared.
Les explains that Genesis 22 contains the account of the ram caught in the thicket, so Abraham did not have to kill Isaac after all. When Abraham realized that the Sovereign God had provided the sacrifice in verse 14, he called that place Jehovah Jireh. Les points out that Jehovah Jireh meant, "I am your provider," and that Jehovah contracted is the I Am; Jireh means provider in the Hebrew. The place name testified to God's provision, and Scripture says, "As it is said to this day, in the mount of the LORD it shall be seen."