וְשֵׁרֵ֕ת בְּשֵׁ֖ם יְהוָ֣ה אֱלֹהָ֑יו כְּכָל־אֶחָיו֙ הַלְוִיִּ֔ם הָעֹמְדִ֥ים שָׁ֖ם לִפְנֵ֥י יְהוָֽה׃
then he shall minister in the name of the LORD his God, as all his brethren the Levites do, who stand there before the LORD.
Read kabbalistic (mystical) interpretation of Deuteronomy 18:7: and classical mystical sources.