What does Genesis 37:27 mean?

Joseph's brothers had planned to kill him. The oldest, Reuben, argued against it, urging them to throw him alive into a nearby pit. The intent for most of the brothers seems to have been leaving Joseph to die in the wilderness without killing him themselves. Reuben, however planned to come back and free him (Genesis 37:12–24).

Now, however, Judah comes up with another idea: Sell Joseph as a slave to the traders passing on their way to Egypt (Genesis 37:25–26). He argues this has as double benefit. First, they would gain a profit on the sale of their hated younger brother (Genesis 37:3–4). Also, they would avoid the bloodguilt of killing their own family member either directly or indirectly.

It's unlikely Judah means to spare Joseph out of any sense of guilt. He is not avoiding murder for any sense of morality—this is simply the option providing less risk and more benefit. His brothers agree to sell Joseph to the Ishmaelites. A notable exception is Reuben, who is apparently not present for this exchange. Even if he is, he will not be able to rescue Joseph in time (Genesis 37:29).