וַהֲקִ֨ימוּ כָהֲנַיָּ֜א בִּפְלֻגָּתְה֗וֹן וְלֵוָיֵא֙ בְּמַחְלְקָ֣תְה֔וֹן עַל־עֲבִידַ֥ת אֱלָהָ֖א דִּ֣י בִירוּשְׁלֶ֑ם כִּכְתָ֖ב סְפַ֥ר מֹשֶֽׁה׃ (פ)
Rashi on Ezra
Now they set up the priests in their divisions for the priests were divided in their service and the Levites in their watches.