What does Genesis 37:23 mean?

Finally, Joseph reaches his brothers. They have seen him coming and have been debating how to get rid of him once and for all (Genesis 37:12–20). One source of their fury toward Joseph is their father's blatant favoritism (Genesis 37:3–4). A lavish sign of this favor is the robe given to him by their father. The unique Hebrew words used to describe this garment imply colors, length, and variation. A typical tunic would have been sleeveless and plain; Joseph's is long and ornate. Intricate robes like this one were sometimes worn by the prince of a tribe or nation. The gift of the robe may have indicated that Jacob planned to make Joseph the primary heir and head of the clan.

It's not surprising, then, that the first action taken by the brothers when Joseph arrives is to rip the robe from him. Their intent is to kill him outright. The oldest, Reuben, appeared to suggest they simply leave him to die in a dry well (Genesis 37:21–22). In truth, he plans to sneak Joseph out to return him to their father.