To fulfill your vow, you must not consume intoxicating, stimulating, depressant, or hallucinogenic substances, including alcohol, caffeine, and other drugs. If you intentionally break your vow, you immediately and irrevocably lose the benefit of this feat. You may not take another feat to replace it. If you break your vow as a result of magical compulsion, or otherwise unintentionally (a drug slipped into your drink, for example), you lose the benefit of this feat until you perform a suitable penance and receive an atonement spell.