As a point of clarification, the Catholic Church does not re-baptize ANYBODY.
In fact, in cases such as with the LDS group, Jehovah’s Witnesses, and other groups, the baptism was not validly administered in the first place, so therefore, they were not, in the eyes of the Church, baptized in the first place.
This is not a matter of trying to disrespect one group or another, but is a matter of a theological difference.
The matter of baptism is water. There are “Christian” groups that do not believe that baptism in water is necessary (most of these groups believe that a “Holy Ghost” baptism renders a water baptism unnecessary).
The form of baptism is the Trinitarian formula given in Matt 28:19. There are some groups that do not baptize using that formula (baptizing “in the name of the Lord Jesus” or some such). There are other groups who do not share the Christian understanding of the Blessed Trinity, as stated in the Scriptures and clarified through the Ecumenical Councils, particularly Nicea I and Chalcedon. (particular examples come to mind are LDS, Jehovah’s Witnesses, and United Pentacostals — but there are others, as well).
Catholic doctrine allows for the recognition of any valid baptism. However, if either the form or matter of a “baptism” were invalid, the baptism would be considered invalid (and therefore not having occurred).
Hopefully that clarifies the issue some.
“Catholic doctrine allows for the recognition of any valid baptism”
Here is a little more on their Mormon answer.
>”Summing up, we can say: The Baptism of the Catholic Church and that of the Church of Jesus Christ of Latter-day Saints differ essentially, both for what concerns faith in the Father, Son and Holy Spirit, in whose name Baptism is conferred, and for what concerns the relationship to Christ who instituted it. As a result of all this, it is understood that the Catholic Church has to consider invalid, that is to say, cannot consider true Baptism, the rite given that name by the Church of Jesus Christ of Latterday Saints.”<
Taken from:
L’Osservatore Romano
Weekly Edition in English
1 August 2001, page 4
L’Osservatore Romano is the newspaper of the Holy See.