"The idea that all truths are equal, all religions are equal, and therefore all morals have equal dignity, that every conscience is valid in its own way, that everyone can judge theologically what they can do, all these are humanistic ideas of total laxity without any discipline of thought, which lead to the position that everyone can do as they please. All this is absolutely contrary to our Catholic Faith."
January 1, 1970
https://en.wikiquote.org/wiki/Marcel_Lefebvre