CCC 1272

Incorporated into Christ by Baptism, the person baptized is configured to Christ. Baptism seals the Christian with the indelible spiritual mark (character) of his belonging to Christ. No sin can erase this mark, even if sin prevents Baptism from bearing the fruits of salvation.⁸² Cf. Rom 8:29; Council of Trent (1547): DS 1609-1619DS — Denzinger–Schönmetzer (Enchiridion Symbolorum). Given once for all, Baptism cannot be repeated.