Trust in Jesus is the essence of the message of mercy. When we go to a public fountain, we can draw water from it as long as we have a vessel or container of some kind to put the water in. If our vessel is small, we can only bring back a little water; if it’s large, we can bring back a lot. And anyone with a vessel can draw water from the fountain. The water is there for us, and no one is excluded. All we need is a vessel.

So it is with God’s mercy. In repeated revelations to St. Faustina, Our Divine Savior makes it clear that the fountain is His Heart, the water is His mercy, and the vessel is trust.

I have opened My Heart as a living fountain of mercy. Let all souls draw life from it. Let them approach this sea of mercy with great trust (Diary, 1520). On the cross, the fountain of My mercy was opened wide by the lance for all souls — no one have I excluded! (1182). I am offering people a vessel with which they are to keep coming for graces to the fountain of mercy. That vessel is this image with the signature: "Jesus, I trust in You" (327). The graces of My mercy are drawn by means of one vessel only, and that is — trust. The more a soul trusts, the more it will receive (1578).

In the Diary of St. Faustina, we hear Our Lord reminding us that we can depend upon His love … that He alone is worthy of our trust: I never reject a contrite heart (1485). Sooner would heaven and earth turn into nothingness than would My mercy not embrace a trusting soul (1777).