Numbers 7:48

On the seventh day Elishama the son of Ammihud, prince of the children of Ephraim, offered:

On the seventh day. Surprise has been expressed by some that this work of presentation was continued on the Sabbath. But assuming that the seventh day referred to was a Sabbath (which is uncertain), the work was of a directly religious character, and perfectly in accordance with the design of the sacred day.