On the Unity of the Catholic Church 20

Nor let anyone be surprised, dearest brothers, that even some of the confessors go on to such things, and that some of them too sin so wickedly, so grievously. For confession does not make a man immune from the snares of the devil, nor, while he is still placed in the world, does it defend him with perpetual security against worldly temptations, dangers, attacks, and assaults; otherwise we would never afterwards see in confessors the frauds, debaucheries, and adulteries which we now see in some, and groan and grieve. Whoever that confessor is, he is not greater or better or dearer to God than Solomon; and yet Solomon, as long as he walked in the ways of the Lord, kept the grace he had obtained from the Lord; after he forsook the Lord's way, he lost the Lord's grace too. And therefore it is written: "Hold fast what you have, lest another take your crown." The Lord surely would not threaten that the crown of righteousness could be taken away, unless, when righteousness departs, the crown must depart too.