A man is also a thief when he conceals his soul’s unseen evil behind a seemingly virtuous way of life, and disguises his inner disposition with an affected innocence. Just as one kind of thief filches his audience’s mind by uttering words of wisdom, so this kind pilfers the senses of those who see him by his pretense of virtue. To him it will be said: ‘Be ashamed of yourselves, all you who are dressed in clothes that do not belong to you’ (Zephaniah 1:8), and : ‘In that day the Lord will reveal their pretense’ (Isaiah 3:17).
I seem to hear God saying these things to me daily in the hidden workshop of my heart, and feel that I am explicitly condemned on both counts.
~St Maximos the Confessor
Prayerful Life 