In the Church of Rome it is held that a spiritual sign, called character, is impressed in the soul by certain sacraments. Aquinas taught that, "in consequence of the death of Jesus, the sacraments instituted in the New Testament have obtained what is called virtus instrumentalis, or effectiva, which those of the Old Testament did not possess. Therefore, by partaking of the sacraments, man acquires a certain character, which, in the case of some sacraments, such as baptism, confirmation, and the ordination of priests, is character indelebilis, and, consequently, renders impossible the repetition of such sacraments"(Aquinas, Summa, pt. 3, Qu. 60-65).
The Council of Florence (1439) laid down the following canon (Mansi, t. 31, col. 1054 sq.): Inter haec sacramenta tria sunt, baptismus, confirmatio et ordo, quse characterem, i.e. spirituale quoddam signum a caeteris distinctivum imprimunt in anima indelebile. Unde in eadem persona non reiterantur. Reliqua vero quatuor characterem non imprimunt, et reiterationem admittunt. — "Among the sacraments there are three, baptism, confirmation, and orders, which impose in the soul a character, that is, a certain spiritual and indelible sign, distinguishing it from others. Hence, in the same persons, these sacraments are not repeated. The other four do not impress a character, and admit of repetition." The Council of Trent gives the following: "9. Whoever shall affirm that a character, that is, a certain spiritual and indelible mark, is not impressed on the soul by the three sacraments of baptism, confirmation, and orders, for which reason they cannot be repeated, let him be accursed" (sess. 7, can. 9). There is a great variety of opinions (naturally enough) among Romanist theologians concerning the nature of this "character." See Ferraris, Promta Bibliotheca, 8:221 (s.v. Sacramentum); Elliott, Delineation of Romanism, bk. 2, ch. 1.