Here are a few observations on Jacob’s blessings in Gen 49. I don’t know what the implications are; these are simply observations on the imagery and rhetoric of the different blessings.
1) The contrast between the rhetoric of curse and the rhetoric of blessing is striking. Reuben, Simeon, and Levi all receive curses because of their sins, and the curses are phrased in sharp, straightforward, non-imagistic and unpoetic language. There are a few metaphors (Reuben is “unstable as water”), but mainly it is simply a literal description of what they did and of what will happen to them. By contrast, the blessings drip with rich imagery.
2) In particular, the blessings often describe the sons of Israel by metaphorical comparisons to animals. “Judah is a lion’s whelp” (v 9); “Issachar is a strong donkey” (v 13); “Dan shall be a serpent in the way” (v 17); “Naphtali is a doe let loose” (v 21); “Benjamin is a ravenous wolf” (v 27).3) The blessing of Joseph is unusual in a couple of respects. First, instead of animal imagery, Joseph is described in terms of vegetable imagery: “Joseph is a fruitful bough, a fruitful bough by a spring; its branches run over a wall” (v 22) – clearly a garden-paradise image. Second, though, much of the blessing is fairly literal; especially in vv 25-26 the description of blessings is straightforward. In other words, the rhetoric of the blessing of Joseph is in some ways closer to the rhetoric of the curses at the beginning of the chapter. (Some of the other blessings are more literal too ?EZebulun [v 13], Gad [v 19], and Asher [v 20].)