A cool, blue radiance pours forth from your extended holy symbol, increasing your power against the foul scourge of the undead.

When you cast light of wisdom upon your holy symbol, your effective turning level increases by 1 per three caster levels.

These bonus levels apply only for the purpose of determining the most powerful undead that your turning check can affect and whether or not the undead you turn are destroyed outright.

The increase has no bearing on the amount of turning damage you deal with a successful turn attempt.