a possible 6th level cleric spell

Here's an idea I was thinking of for that 6th level divine spell from my last post.

Voice of God

Range: Hearing
Duration: Instant
Description:  The caster speaks the true language of their god(s) which causes all who hear it to take 2d6 damage and be deaf for 2d6 rounds.  In addition, creatures and entities opposed to the casters religion (e.g. undead, spirits, minor devils, lawful clerics) suffer the effects of Turn Undead/Cause Fear.  In addition, opposed creatures of less than 2 HD must make a magic resist check or be destroyed and opposed creatures of higher HD but still less than the caster's level must save or take 4d6 +1/ caster's level damage.