St. Faustine describes failing greatly when trying to perfect a virtue. Although we should work hard to develop virtue, our progress is dependent on grace. If we do not cooperate with God, we will be frustrated and fail.

St. Faustina

“When one day I resolved to practice a certain virtue, I lapsed into the vice opposed to that virtue ten times more frequently than on other days. In the evening, I was reflecting on why, today, I had lapsed so extraordinarily, and I heard the words: ‘You were counting too much on yourself and too little on Me.’ And I understood the cause of my lapse.”

Source:ÿ St. Faustina, Diary: Divine Mercy in My Soul