There's more things that i like about the Lion Turtle. For example, it says to Aang:

"Since beginningless time, darkness thrives in the void, but always yields to purifying light."

What does that mean? What is the purifying light that the Lion Turtle talks about? Is there, maybe, a psychological state which conquers the harmful behavior without exercising violence?

Maybe that message only makes sense to Aang, because he's an air nomad and believes in these ways. Maybe the Lion Turtle would have said something different to a water bender, or to another person in general.

What would the Lion Turtle have said in that case?