Jesus said later to Saint Faustina:

“Say unceasingly this chaplet that I have taught you. Anyone who says it will receive great Mercy at the hour of death. Priest will recommend it to sinners as the last hope. Even the most hardened sinner, if he recites this chaplet even once, will receive grace from My Infinite Mercy. I want to give unimaginable graces to those who trust in My Mercy.”