It's just a foreshadowing of the Messiah. It's not needlessly complicated, nor is it difficult to understand. But that's the way the scriptures were designed -- to be understood by those who sought understanding and to be confusing to those who lack the desire.
Josephus quotes Abraham's explanation to his son:
“Oh, son, I poured out a vast number of prayers that I might have thee for my son; when thou wast come into the world, there was nothing that could contribute to thy support for which I was not greatly solicitous, nor anything wherein I thought myself happier than to see thee grown up to man's estate, and that I might leave thee at my death the successor to my dominion; but since it was by God's will that I became thy father, and it is now his will that I relinquish thee, bear this consecration to God with a generous mind; for I resign thee up to God who has thought fit now to require this testimony of honor to himself, on account of the favors he hath conferred on me, in being to me a supporter and defender. Accordingly thou, my son, wilt now die, not in any common way of going out of the world, but sent to God, the Father of all men, beforehand, by thy own father, in the nature of a sacrifice. I suppose he thinks thee worthy to get clear of this world neither by disease, neither by war, nor by any other severe way, by which death usually comes upon men, but so that he will receive thy soul with prayers and holy offices of religion, and will place thee near to himself, and thou wilt there be to me a successor and supporter in my old age; on which account I principally brought thee up, and thou wilt thereby procure me God for my comforter instead of thyself.” (Antiquities of the Jews, I:13:3.)
We don't know the source of this account, but it's significant in more than explaining Abraham's reasoning. Josephus was not a Greek, but a devout Jew. In the above account, which is clearly Jewish in nature, we see what the Christian and the Jews taught. First, that God is the Father of all men, not just the creator. Second, it soundly belies the doctrine that the souls of men sleep when they die. The author of the above, whoever he was, clearly believed that had Isaac suffered death, his soul would return to God and be near unto Him, and that he, Isaac, would be a "successor and supporter" to him after death. Thus, Isaac's spirit would return to God, the Father of all men, and there be able to watch over his father in old age.
The Adventist doctrine of soul sleeping is therefore dealt a decisive blow because the source of the above came from a Jew who was quoting it from an earlier Jewish source. It thus proves that the concept of man's having a spirit is not a Greek invention. And that proves that the Watchtower Bible and Tract Society is dead wrong on one of its CHIEF doctrines.
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