וַיִּפְקֹ֨ד מֹשֶׁ֧ה וְאַהֲרֹ֛ן וּנְשִׂיאֵ֥י הָעֵדָ֖ה אֶת־בְּנֵ֣י הַקְּהָתִ֑י לְמִשְׁפְּחֹתָ֖ם וּלְבֵ֥ית אֲבֹתָֽם׃
And Moses and Aaron and the princes of the congregation numbered the sons of the Kohathites by their families, and by their fathers’houses,
Read kabbalistic (mystical) interpretation of Numbers 4:34: and classical mystical sources.