Deuteronomy 33:8

Thy Thummim and thy Urim be with thy holy one; the Thummim and the Urim, which are thine, O Lord, by special institution and consecration; by which he understands the ephod, in which they were put, Exodus 28:30, by a synecdoche, and the high priesthood, to which they were appropriated, by a metonymy; and withal the gifts and graces signified by the Urim and Thummim, and necessary for the discharge of that high office, shall be with thy holy one, i.e. with that Levite, that priest, which thou hast consecrated to thyself, and which is holy in a more peculiar manner than all the people were, i.e. the priesthood shall be confined to and continued in Aaron's family. Whom thou didst prove: this seems added by way of anticipation; although thou didst try him, and rebuke him, and shut him out of Canaan for his miscarriage about fetching water out of the rock, yet thou didst not therefore take away the priesthood from him. At Massah; not at that Massah mentioned Exo 17, which is also called Meribah, where neither Moses nor Aaron are reproved, nor is Aaron so much as named, but at that other Meribah, Num 20, where this is expressed, which as it is called by one of the names of that place, Exo 17, to wit, Meribah, Num 20, so it may be here called by its other name, Massah; and well may the same names be given to those two places, because the occasion of them was in a great measure one and the same. Though this place may be otherwise rendered, whom thou didst try in trying, or with trial, i.e. whom thou didst exactly and thoroughly try, such repetitions being very frequent and elegant in the Hebrew language. And it may be observed, that in the Hebrew text here are two several prepositions, though the English translation render them both by at, here beth, in or with, and in the next branch al, at, or near, or concerning the waters of Meribah; which may seem to intimate that the former is not the name of the place, as the latter is: why else should they not have been expressed by the same preposition? With whom thou didst strive, or, contend, i.e. whom thou didst reprove and chastise, as that phrase signifies, Isaiah 49:25 Jeremiah 2:9.