SRD:Phylactery of Faithfulness

Phylactery of Faithfulness: This item is a small box containing religious scripture affixed to a leather cord and tied around the forehead. There is no mundane way to determine what function this religious item performs until it is worn. The wearer of a phylactery of faithfulness is aware of any action or item that could adversely affect his alignment and his standing with his deity, including magical effects. He acquires this information prior to performing such an action or becoming associated with such an item if he takes a moment to contemplate the act.

Faint divination; CL 1st; Craft Wondrous Item, detect chaos, detect evil, detect good, detect law; Price 1,000 gp.