Commentary for II Chronicles 30:17

כִּי־רַבַּ֥ת בַּקָּהָ֖ל אֲשֶׁ֣ר לֹא־הִתְקַדָּ֑שׁוּ וְהַלְוִיִּ֞ם עַל־שְׁחִיטַ֣ת הַפְּסָחִ֗ים לְכֹל֙ לֹ֣א טָה֔וֹר לְהַקְדִּ֖ישׁ לַיהוָֽה׃

For there were many in the congregation that had not sanctified themselves; therefore the Levites had the charge of killing the passover lambs for every one that was not clean, to sanctify them unto the LORD.

Rashi on II Chronicles