Do you know if a person from another faith tradition has to be baptized again to be received into the Catholic church?
Baptism happens just once in a lifetime. The Sacrament of Baptism changes us, linking us with the communion of believers, making us part of “a royal priesthood, a holy nation” (Peter 2:0). That change can never be wiped away. Because of this, the Catholic Church never repeats this sacrament. Baptism administered in other Christian churches, with the pouring of water and the words “I baptize you in the name of the father, and of the Son, and of the Holy Spirit,” (Christian Initiation, Gen. Intro,. 23) is honored in the Catholic church. The sacrament is the same even for many churches that are not in full communion with the Catholic church.
Rite of Christian Initiation of Adults