Etymology of "Daysman."

What is the etymology of *Daysman*, which, in the Book of Job, and in some of our provincial dialects, means a mediator or arbitrator? [NARES defines *Daysman*, an umpire or arbitrator, from his fixing a day for decision; and adds, "Mr. Todd shows that *day* sometimes meant Judgment." Jacob, in his *Law Dictionary*, tells us, "Days-man signifies, in the North of England, an arbitrator or person chosen to determine an affair in dispute, who is called a *Dies-man* or *Days-man*." Jacob's definition may be again illustrated from NARES: —"In Switzerland (as we are informed by Simlerus) they had so…