זָר שֶׁעָבַד בַּמִּקְדָּשׁ עֲבוֹדָתוֹ פְּסוּלָה וְחַיָּב מִיתָה בִּידֵי שָׁמַיִם שֶׁנֶּאֱמַר (במדבר יח ז) "וְהַזָּר הַקָּרֵב יוּמָת" מִפִּי הַשְּׁמוּעָה לָמְדוּ שֶׁאֵין חִיּוּב זֶה אֶלָּא לִקְרַב לַעֲבוֹדָה. וְהֵיכָן הִזְהִיר עָלָיו וְזָר לֹא יִקְרַב אֲלֵיכֶם. אֵי זֶהוּ זָר כָּל שֶׁאֵינוֹ מִזֶּרַע אַהֲרֹן הַזְּכָרִים שֶׁנֶּאֱמַר (ויקרא א ח) "וְעָרְכוּ בְּנֵי אַהֲרֹן". וְהִקְטִירוּ בְּנֵי אַהֲרֹן. בְּנֵי אַהֲרֹן וְלֹא בְּנוֹת אַהֲרֹן:
When a non-priest serves in the Temple, his service is invalid and he is liable for death at the hand of heaven, as [Numbers 18:7] states: "A non-priest who draws close will die." According to the Oral Tradition, we have learned that one does not become liable unless he draws close to perform service. Where is the warning concerning this? [Ibid.:4] states: "A non-priest shall not draw close to you." What is meant by a non-priest? Anyone who is not a male descendant of Aaron, as [Leviticus 1:8] states: "And the sons of Aaron shall arrange" and [Leviticus 3:8] states: "And the sons of Aaron shall set afire." [These service are performed by] "the sons of Aaron" and not the daughters of Aaron.
