Isaiah 58:13-14.
Commands divine worship.
LIKEWISE the people of the land shall worship at the door of this gate be for the Lord in the sabbaths and in the new moons.
Ezekiel 46:3
Required His word to be read.
FOR they that dwell at Jerusalem, and their rulers, because they knew him not, nor yet the voices of the prophets which are read every sabbath day, they have fulfilled them in condemning him.
Acts 13:27.
The Lords Supper to be observed.
AND upon the first day of the week, when the disciples came together to break bread, Paul preached unto them, ready to depart on the morrow; and continued his speech until midnight.
Acts 20:7.