Quote Originally Posted by Rater202 View Post
Not quite.

In this situation, there's no choice to be made.

The player has been killing slavers wherever they find them for the entire campaign and it has not been a problem, and this is maybe the halfway point.
There's always a choice to be made. Players aren't slaves.

On many an occasion I have had a character behave inconsistently for the sake of the fun of the other players at the table.

If you chose to behave as if your character's "holy consistency" is more important than the table at large, that is entirely on you. It's a choice and you have made it.