We are often tempted to respond to someone's actions (or purposeful inaction) by telling them to go to hell. "Consign" basically means 'send to'...
You've done, I've done it...
Desertman is saying, in my opinion, that we ought not to do it because it might turn out that we will, for one reason or another, have to go fetch them back, which will mean we will be in hell.
It's practical, logical, thoughtful thinking, as opposed to hot blooded, judgmental, punitive thinking.
Personally, I tend very much to follow it. I don't have the 'maturity' for hatred; I prefer just moseying along, doing my thing, loving my people, and sleeping late in the mornings.