The Bab and the law of tattoo

We have already seen how in the Persian Bayán cleanliness and beautification is emphasized as a means of spiritualizing the material body. The Báb even allows the believers to have a tattoo on their bodies: since the heart is the seat of the love of God, the Báb states that it is permitted that the phrase “O Thou My God” (Alláhumma), for males, and “the Most Gracious” (ar-Rah.mán), for females, be inscribed on their chests, in the most beautiful of calligraphy. (Persian Bayan 8:6) 

(Gate of the Heart, Understanding the Writings of the Báb – Nader Saiedi P.329)