DAYSMAN (Heb yākhah, to act as umpire). A mediator or arbitrator—one who has set a day for hearing a dispute. As used in Job.9.33 (kjv; niv “someone to arbitrate”), the word means an umpire or referee who hears two parties in a dispute and decides the merits of the case. In eastern lands it was the custom for the judge to put his hands on the heads of the two parties in disagreement to show his authority and his desire to render an unbiased verdict. Job’s statement means that no human being is worthy of acting as judge of God.
. KJV word for Umpire
International Standard Bible Encyclopedia (1915)
(yakhach, "to argue, decide, convince," the Revised Version (British and American) UMPIRE): The use of this word appears to have been more common in the 16th century than at the later date of the translation of the King James Version, when its adoption was infrequent. The oldest instance of the term given in the Oxford English Dictionary is Plumpton Corresp. (1489), p. 82: "Sir, the dayesmen cannot agre us." It appears also in the 1551 edition of the Old Testament in 1Sa 2:25, where the English Versions of the Bible "judge" is translated "dayes-man." Tyndale’s translation has for Ex 21:22, "He shall paye as the dayesmen appoynte him" (EV as the "judges determine"). See also Edmund Spenser’s Faerie Queene, ii, c. 8, published in 1590. As used in the King James Version (Job 9:33) the word means an arbitrator, umpire, referee; one who stands in a judicial capacity between two parties, and decides upon the merits of their arguments or case at law. "Neither is there-any daysman (the Revised Version (British and American) "umpire") betwixt us, that might lay his hand upon us both" (compare Ge 31:37). It was the eastern custom for a judge to lay his hands upon the heads of the two parties in disagreement, thus emphasizing his adjudicatory capacity and his desire to render an unbiased verdict. Job might consider a human judge as capable of acting as an umpire upon his own claims, but no man was worthy to question the purposes of Yahweh, or metaphorically, to "lay his hands upon" Him.
In the New Testament (1Co 4:3, anthropine, hemera) "man’s judgment" is literally, "man’s day," in the sense of a day fixed for the trial of a case. Both Tyndale and Coverdale so translate. See also 1Ti 2:5, where the Saviour is termed the "one mediator .... between God and men." Here the word understands a pleader, an advocate before an umpire, rather than the adjudicator himself (see Job 19:25-27).