unstamp

Verb

 * 1)  To undo the act of stamping something; to remove a stamp from.
 * 2) * 1843, James Garbett (Archdeacon of Chichester), Parochial Sermons (volume 1, page 267)
 * At present let man sin as he may, and strive as he will, to unstamp his soul of the seal of God upon it, and the superscription of original virtue, he cannot do it.