Catholic theology
Catholic belief holds that the church exists both on earth and in heaven simultaneously, and thus the Virgin Mary and the saints are alive and part of the living church. Prayers and devotions to Mary and the saints are common practices in Catholic life. These devotions are not worship, since only God is worshiped. The church teaches that the saints "do not cease to intercede with the Father for us. ... So by their fraternal concern is our weakness greatly helped."
Worship
Mass is the central act of divine worship in the Catholic Church. The Congregation for Divine Worship at the Vatican publishes a "Directory on Popular Piety and the Liturgy". Roman Catholic devotions are "external practices of piety" which are not part of the official liturgy of the Catholic Church but are part of the popular spiritual practices of Catholics. They do not become part of liturgical worship, even if conducted in a Catholic church, in a group, in the presence of a priest.