Learning to pray the Divine Mercy, to foster a love for it, to promote it all stems from a great devotion revealed by Saint Maria Faustina Kowalska. Let me say something in regards to devotion in light of public worship.
Public worship is best lived out in the Mass. The Mass is the gathering of God’s people around his altar of the Word and Eucharist where they experience conversion, silence, proclamation, and are fed with the Bread of Life. This public worship is central to God’s people for it is their source and summit. Devotion overflows from this like water that overflows from a cup. Devotion flows back into the public worship of God.
We as the baptized are bound to public worship as a duty of being Christian. Devotions such as the Divine Mercy always orient us back to the Sacred Liturgy, gives depth and deeper understanding to the liturgy.
Furthermore, devotions do not reveal anything new about scripture or sacred tradition. Rather, devotions give God’s people a deeper appreciation of who God is in his Church. They orient us back to the Sacred Liturgy where truth breathes and lives.
So a devotion to Divine Mercy brings must always bring us to a deeper love for the Eucharist!