“There are people—and there were especially many during pagan times—who rely entirely upon themselves and think that everything is achievable through the powers of their minds and feelings. They do not understand that many things, in fact the most important, precious and cherished things, are not accessible to our minds and feelings..The strength to do good works, like the strength to be freed from vices, is something we receive only from God.”
(St. Luke of Crimea quoted in pravoslavie.ru)