1. Third Commandment
Keep holy the Sabbath

2. Sabbath in the Old Testament
Seventh day – Genesis
Laws for the observance of the Sabbath – Exodus
Sabbath consecrated to God – Leviticus
Sacrifices to be performed (bread of proposition) (Numbers), tasks to be avoided (cooking food, lighting a fire, etc.)

3. Purpose of the Sabbath Day to worship Yahweh Day of rest
Celebrated by the Jews on Saturday (sundown Friday to sundown on Saturday)
(Muslims celebrate their day of worship on Fridays)

4. Lord’s Day in the New Testament
At first celebrated on Saturday and Sunday simultaneously.
Gradually shifted to the “first day of the week
Name changed to “The Lord’s Day

5. Christian Sunday
Easter was celebrated on Sundays as early as the second century as reported in the Didache (an early text).
Early celebrations were private due to fear of persecution.
In 321, Emperor Constantine recognized the Christian religion and celebrations were public.
The emperor also forbade servile work and other public activities.

6. Obligation to attend mass
Since Sunday commemorates the death and resurrection of Jesus Christ, it is the day on which the church celebrates the paschal mystery. The “faithful are bound to come together in one place, listen to the word of God, and take part in the Eucharist.
Two origins
The obligation of giving worship to God one day during the week
The importance of the Eucharist

7. Holy Days of Obligation
According to the Code of Canon Law, Sunday is the primary holy day of obligation.
On Sundays, we are obliged to participate in the Mass and to avoid “servile” work.
Canon Law lists ten days as holy days of obligation for the universal church,

8. Holy Days of Obligation in the U.S.
The following solemnities are the holy days of obligation (according to the bishops) in the U.S:
Mary, the Mother of God (Jan. 1)
The Ascension of Jesus (40 days after Easter, transferred to the following Sunday, the 7th Sunday after Easter)
The Assumption of Mary (Aug. 15)
The Feast of All Saints (Nov. 1)
The Immaculate Conception (Dec. 8)
Christmas (Dec. 25)
The Feast of the Epiphany and the Feast of the Body and Blood of Christ (Corpus Christi) have been transferred to the Sundays following these feasts.
The feast of St. Joseph and the feast of Sts. Peter and Paul are not celebrated (are suppressed) as holy days in the U.S.

9. Fulfilling the precept of attending Mass
The obligation to attend Mass is a serious one.
There must be a serious reason to miss Mass – illness, the care of infants or the sick, dispensation by a priest.
The obligation can be met by attending a vigil mass (a mass that has the readings of the Sunday liturgy)
The obligation calls for “participation” in Mass.

10. Work on Sunday Work should not be undertaken on Sunday if the work
Impedes participation in Mass
Inhibits the ability to “restore” ourselves
Makes bodily or mental rest impossible
Work that may be necessary on Sundays
health care, law enforcement, military, fire departments, priests and ministers, people who keep farms or livestock, etc.