Are you a Methodist? A Southern Baptist? Perhaps you attend a non-denominational church?
Well, according to the Council of Trent, held from 1545 to 1563, you’re a heretic.
The heretical belief here is that Protestant denominations deny the infallible authority of the Catholic Church, and hold the position that each individual is to interpret Scripture personally.
And this isn’t just a decree that’s relegated to the history books. As recent as the 1960s, Pope John XXIII declared that “What was, still is,” concerning the findings of the Council of Trent.
This world's most popular heresy affects more than 900 million Christians worldwide, and although most Catholics would never label individual Protestants formal heretics, the idea that Protestantism is heretical still stands.
So why isn’t this one so bad? Well, mostly because there is no real scriptural basis for this heresy. What is perceived to be the great error of Protestantism—sola scriptura, the idea that only the Bible should be used when forming theology—may actually be a strength. Acts 20:32 reads, “And now I commend you to God and to the word of His grace, which is able to build you up and give you the inheritance among all those who are sanctified.”
It seems that the ideas of Protestantism are justified—not only in Acts, but throughout scripture. With verses like that to cast doubt on the protestant controversy, it’s unlikely that charges of heresy should bother the hearts and minds of Protestants.