Divine Shield

(Complete Warrior, page 106, DnD 3.5)

[Divine]

You can channel energy to make your shield more effective for either offense or defense.

Prerequisite

Turn or rebuke undead ability, Proficiency with a shield

Benefit

As a standard action, spend one of your turn/ rebuke undead attempts to channel energy into your shield, granting it a bonus equal to your Charisma modifier. This bonus applies to the shield's bonus to Armor Class and lasts for a number of rounds equal to half your character level.