Assurance: The Greatest of all Protestant Heresies

Cardinal Robert Bellarmine (1542–1621) was a figure not to be taken lightly. He was Pope Clement VIII’s personal theologian and one of the most able figures in the Counter-Reformation movement within sixteenth-century Roman Catholicism. On one occasion, he wrote: “The greatest of all Protestant heresies is assurance.”

By Sinclair Ferguson
http://www.ligonier.org/blog/what-greatest-all-protestant-heresies/