A Catholic priest seems like an unusual character for this time period. This is set in the mid-late Twenties, right? The persecution and de facto outlawing of the Catholic Church in Mexico that started in 1917 reached a fever pitch by this point and would not subside until 1940. If Father Mateo were to walk outside his church (which would probably have been looted already) wearing a clerical collar he would most likely have been arrested and shot.