Notice how God phrases this: "your only son [the only legitimate son] . . . whom you love." It is not that Abraham does not love Ishmael, but Isaac is the son of promise, the son of his old age, a very special son. God is tender in His phrasing, for what he commands Abraham to do foreshadows Christ's own sacrifice later and so has special meaning to God.
There was absolutely nothing wrong in Abraham loving Isaac deeply, as long as his love did not become worship. We often say we "adore" those whom we love. The first definition of adore is "to worship with divine honors," while the second is "to love deeply," which is perfectly acceptable to do. It is important to understand the distinction.
God tells Abraham, "Go to the land of Moriah," and He promises to tell him exactly which peak he should ascend. "Moriah" refers to an area of land in what is now Jerusalem that contains several mountains or small peaks. Abraham lived in Beersheba, more than 40 miles from Moriah.
God also tells him to sacrifice Isaac "as a burnt offering." We can only imagine the thoughts that must have raced through Abraham's mind! How can the promises be fulfilled if Isaac is dead? Is this not human sacrifice, such as was practiced by the heathen nations? Would this not be murder? How will it look to Sarah, his servants, the Egyptians, and others? Even so, his obedience was absolute.
Abraham's One God