I am currently an active Mormon who is studying the Catholic Church. I was previously baptized as a teen in a Protestant Church. If I should decide to convert to the Catholic Church would I need to officially resign from the LDS Church or just leave as I did when I converted from Presbyterian to Mormon?
No. From the Catholic Church’s perspective, when a person from another church becomes a Catholic, by that fact, he or she is no longer belongs to the former church.
Fr. Vincent Serpa, O.P.