17 Thummim and Urim. These terms, whose meaning is uncertain, refer to sacred stones carried in a pouch on the breastplate of the high priest and examined on occasion as a means of ascertaining God’s will or direction. See Exod 28:30; Lev 8:8; Num 27:21; 1 Sam 28:6. See also C. Van Dam, 1:.
18 Heb “godly man.” The reference is probably to Moses as representative of the whole tribe of Levi.
19 Massah means “testing” in Hebrew; the name is a wordplay on what took place there. Cf. Exod 17:7; Deut 6:16; 9:22; Ps 95:8–9.
20 Meribah means “contention, argument” in Hebrew; this is another wordplay on the incident that took place there. Cf. Num 20:13, 24; Ps 106:32.

In other versions

And of Levi he said,

“Give to Levi your Thummim,

and your Urim to your godly one,

whom you tested at Massah,

with whom you quarreled at the waters of Meribah;

About Levi he said:

“Your Thummim and Urim belong

to your faithful servant.

You tested him at Massah;

you contended with him at the waters of Meribah.

He said about Levi:

Your Thummim and Urim belong to your faithful one;

you tested him at Massah

and contended with him at the Waters of Meribah.

Moses said this about the tribe of Levi:

“O Lord, you have given your Thummim and Urim—the sacred lots—

to your faithful servants the Levites.

You put them to the test at Massah

and struggled with them at the waters of Meribah.

And of Levi he said,

“Your Thummim and your Urim

are for your faithful one,

whom you tested at Massah;

you contended with him

at the waters of Meribah.

And of Levi he said,

Let thy Thummim and thy Urim be with thy holy one,

Whom thou didst prove at Massah,

And with whom thou didst strive at the waters of Meribah;

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