Numbers 28:10

This is the burnt offering of every sabbath, beside the continual burnt offering, and his drink offering.

The law required for every Sabbath a burnt offering with its drink offering, presented beside and in addition to the continual daily burnt offering. That added Sabbath burnt offering belonged to the sanctuary's special services, standing together with the appointed offerings for new moons and for feasts.

Presenting those offerings increased the priests' work on the Sabbath, yet because it was holy service performed for God it did not violate the fourth commandment. Those temple rites pointed to Christ's redeeming work, so labor in God's service accorded with the Sabbath's own purpose and shows that necessary work for God's redemptive mission may be done on the Sabbath. Such Sabbath service was sacred work for God, wholly distinct from ordinary labor done for a livelihood, for personal gain, or for selfish interest.

As the priests' prescribed Sabbath sacrifices were no violation, so religious work such as writing on the Sabbath is not in itself a violation. The Sabbath sacrificial services thus stand as a model of sacrificial giving back to God.