NOTES for Gen 48:1-22
With the blessing of Joseph's children, the same thing happens that once happened with the blessing of Jacob himself and his brother Esau: Jacob, too, received a blessing that was "not his." True, he obtained that blessing himself, and by deception, while in this case there is no deception to speak of; but the essence of the matter does not change: first place is received not by the one to whom it should have belonged according to custom and established traditions. God often breaks established traditions and human customs, perhaps also so that people will not consider either one something unshakable and coming directly from Him.
Here, incidentally, it also becomes clear how much Jacob's idea of blessing had changed compared with his father Isaac's. For Isaac it is still quite traditional, connected with equally traditional ideas about a power that can be taken or given away, but only once: what has been given away cannot be taken back. For Isaac this power is connected with the God of Abraham; He is its source, but in every other respect blessing, as Isaac understands it, differs practically not at all from a pagan one. Even if he made a mistake, even if God did not want him to give his power to Jacob instead of Esau, and Isaac could well have thought this when he discovered his mistake, nothing could be done: what is given is given. For Jacob himself, however, blessing has become first of all an act of God, while he looks at himself only as an instrument in His hands. He is only the bearer of God's power, in no sense its owner, and he passes it on only to the one whom God indicates.
No one else will be able simply to receive it, for in the final account its owner remains God, and a human being can only be a steward here, free to dispose of it only insofar as his actions do not go beyond the limits of God's plan, God's intentions, and God's will. That is why conflicts like the one that took place when Jacob obtained the blessing by deception now become impossible. And this is no surprise: Jacob really has become not simply the leader of his tribe, but also the leader of the people of God. God made Jacob what He wanted him to be.