Rebuke

Your wrathful words cause physical harm to your enemies. Your enemies take 1d8 points of damage per two caster levels (maximum 5d8) and are staggered for 1 round. Half of this damage is sonic damage, but the other half results directly from divine power and is therefore not subject to being reduced by resistance to sonic-based attacks. Rebuke is especially devastating to foes who worship your god, inflicting 1d6 points of damage per caster level (maximum 10d6) and stunning them for 1d4 rounds. A successful Fortitude save halves the damage and negates the staggering or stunning effect.

Enemies do not need to hear a rebuke to be harmed by it, but it is negated by magical silence.