Both kindness and evilness have a radiant power.
Temptations brought by the devil lead to sins that at first seem sweet but in the end they become bitter passions. Man has its own sweetness that he spreads around. The vicious man becomes sad and through his dark appearance he will make everyone bitter. The good man, on the contrary will make people happy to the measure of his soul. This is why saints transmit spiritual sweetness. The Evil Man Makes Everyone Bitter. Both kindness and evilness have a radiant power. It is the proof that when someone becomes evil, he must have received this influence from unseen evil spirits.
(Translation from Părintele Dumitru Stăniloae, nota 698 la Varsanufie şi Ioan, Scrisori duhovniceşti, în Filocalia XI, Editura Humanitas, Bucureşti, 2009, p. 402)