As for repentance, you'd be surprised at how merciful deities of mercy can be.
I would guess there would still be a heavy penance, not to mention learning the rites of the faith, etc. And, regardless, if I (as the DM-Deity) believed it was done in a premeditated manner to gain some numerical advantage...let's just say it would be easier to continue to be evil and they would have to work hard to truly repent. [/Bastard DM]
Technik