Was not Luther a brave man to follow his convictions despite the opposition of the Catholic Church?

The Catholic Answers

He had a certain natural courage. But that was no more a virtue than the courage often found in evil-doers. I do not maintain that merely human courage is the monopoly of good Christian men. However, I deny that Luther was following his sincere convictions. Rather he followed his passions.

Radio Replies Volume 1 by Rev. Dr. Leslie Rumble MSC and Rev. Charles Mortimer Carty