Catechism of the Catholic Church

The Church obliges the faithful to take part in the Divine Liturgy on Sundays and feast days and, prepared by the sacrament of Reconciliation, to receive the Eucharist at least once a year, if possible during the Easter season. But the Church strongly encourages the faithful to receive the holy Eucharist on Sundays and feast days, or more often still, even daily. (2042, 2837)