וישבות ביום השביעי מכל מלאכתו אשר עשה. And He rested on the seventh day from all his work that he had made. [Genesis] What could this possibly mean? If he stopped working at the beginning of night on Friday night, but then simply did no more work, then it was not on the seventh day alone that he rested by the eight and ninth, and onward. So it must mean He continued working on the eight day in order for the entire seventh day to be one span of an interval of not working.

The Sages ask this and answer since then he makes "Shiduchim," matches-but that does not seem to come under the category of the 39 types of work.