Some days carry obligations.
Birthdays, family reunions, and holidays oblige us to send cards, buy gifts, attend parties, reserve time, telephone, or stop by. Such events make up a calendar of observances whose obligations we honor out of love, even when they cause inconvenience. The Catholic Church also keeps a calendar of special days. On holy days, the church asks us all to participate in the Eucharist. If you go to a birthday party but sit quietly in the back of the room, you have not really participated.