Jesus said to Saint Faustina, "Say unceasingly the chaplet that I have taught you. Whoever will recite it will receive great mercy at the hour of death. Priests will recommend it to sinners as their last hope of salvation. Even if there were a sinner most hardened, if he were to recite this chaplet only once, he would receive grace from My infinite mercy . . . I desire to grant unimaginable graces to those souls who trust in My mercy." (Diary 687) "The souls that will say this chaplet will be embraced by My mercy during their lifetime and especially at the hour of their death." (Diary 754)

The chaplet can be said on ordinary rosary beads. We begin with the Our Father, Hail Mary and the Apostles' Creed.

Then on the 5 large beads:
Eternal Father I offer You the Body and Blood,
Soul and Divinity of Your dearly beloved Son,
Our Lord Jesus Christ, in atonement for our
sins and those of the whole world.

On the 10 small beads:
For the sake of His sorrowful Passion
have mercy on us and on the whole world.

Conclude (3 times) with:
Holy God, Holy Mighty One, Holy Immortal One,
have mercy on us and on the whole world.

Prayed on ordinary rosary beads, the Chaplet is an intercessory prayer that extends the offering of the Eucharist. It may be said at any time, but Our Lord specifically requested that it be used as a novena on the nine days before the Feast of Mercy (Divine Mercy Sunday which is the first Sunday after Easter).

"At the hour of their death, I defend as My own glory every soul that will say this chaplet; or when others say it for a dying person, the indulgence is the same." (Diary 811) "When they say this chaplet in the presence of the dying, I will stand between My Father and the dying person, not as the just Judge but as the merciful Saviour." (Diary 1541)