Since the first few centuries of Christianity, there has existed a Sunday obligation for Catholics to attend Mass. Initially there was no need for a law, since Christians gladly and joyfully embraced God's command.
St. John Paul II explains this in his apostolic exhortation Dies Domini.
The current Code of Canon Law confirms this obligation and states, "On Sundays and other holy days of obligation, the faithful are obliged to participate in the Mass."
This means that any Catholic who is able to attend Mass must make every reasonable effort to be there.
At the same time, the obligation to attend Mass can be dispensed for a grave reason, as the Catechism of the Catholic Church explains.
Other serious reasons should be discussed with an individuals' local pastor, who can give guidance or confirm the dispensation.
Above all, the obligation should not be seen as an "imposition," but an "invitation" to enter into the love of God, as John Paul II reiterated.
The Sunday obligation is a great gift to humanity, and Catholics are called to fulfill it with a joyful heart.
