This prayer was given to St Faustina by Jesus.
You expired, Jesus, but the source of life gushed forth for souls, and the ocean of mercy opened up for the whole world. O Fount of Life, unfathomable Divine Mercy, envelope the whole world and empty Yourself out upon us.
O Blood and Water, which gushed forth from the Heart of Jesus, as a fount of mercy for us, I trust in You. (x3)