The Bible · Church word
Sabbath
In plain words
The weekly day of rest God gave his people.
The fuller definition
The weekly day of rest God gave Israel, the seventh day, kept from Friday evening to Saturday evening. Christians gather on Sunday, the day of the resurrection. Luther taught that the point of the commandment is hearing God’s word gladly, not a rule about a day.
Where it comes from
Exodus 20:8–11; Small Catechism, Third Commandment
In The Bible: Its books, its translations, and how Lutherans read it.