Beware these two thoughts and fear them. The first suggests ‘You are a saint,’ the other, ‘You will not be saved.’ Both come from the enemy, and there is no truth in them. Instead, think to yourself, ‘I am a great sinner but the Lord is merciful. He loves man with a great love and will forgive me my sins.’ Believe in this way, and you will see, the Lord will forgive you. But put no faith in feats of your own, however much you may have striven… Thus God has mercy on us, not for our achievements but gratis, because of His goodness.
~Saint Silouan the Athonite, “Concerning Intrusive Thoughts and Delusions,” Saint Silouan the Athonite, by Archimandrite Sophrony