What makes him different, Barret, is that he is not insane, he is not from the time when he becomes a wanna-be-god-madman-with-delusions-, as well as the fact that the crisis here on Crystallis takes priority over that of the crisis on Gaia. A crisis which Sephiroth is working towards stopping.

[Vincent is glad he can be patient. Yes, Barret can be stubborn, but had he listened to what they'd said?]

You don't need to be friends with him. You don't need to like him. You DO need to let him be and not shoot him, and accept he is a Hero of Light, like the rest of us.