קְדֹשִׁ֤ים יִהְיוּ֙ לֵאלֹ֣הֵיהֶ֔ם וְלֹ֣א יְחַלְּל֔וּ שֵׁ֖ם אֱלֹהֵיהֶ֑ם כִּי֩ אֶת־אִשֵּׁ֨י יְהוָ֜ה לֶ֧חֶם אֱלֹהֵיהֶ֛ם הֵ֥ם מַקְרִיבִ֖ם וְהָ֥יוּ קֹֽדֶשׁ׃
santos serão para seu Deus, e não profanarão o nome do seu Deus; porque oferecem as ofertas queimadas do SENHOR, que são o pão do seu Deus; portanto serão santos.
Shenei Luchot HaBerit
Commandment 265 forbids a priest who has purified himself -but still awaits sunset after ritual immersion- to perform sacrificial service. At that point he is still in the state of a secondary degree of ritual impurity. Concerning this the Torah writes: ולא יחללו שם אלוקיהם (21,6). Sanhedrin 83 explains that as the verse is not needed, because the information contained in it is already known, it is available to derive additional laws of a related matter, in this case the continued טומאה status of someone awaiting the sun to set after he has completed the ritual of purification. The similarity of the expressions חילול on both occasions lends weight to the validity of this rule.