This Gemara discuses a well known principle of אין שבות במקדש there are no rabbinic restrictions within the Temple.  The basic understanding of why this is true, is because the Cohanim are zealous and thus would be unlikely to make a mistake (רבנו יהונתן ערובין קב א).  In Other words, the priest, especially in the Holy Temple site, do not require extra strength and cease to protect them from inadvertent violation; the biblical law alone is sufficient. There are variations on this theme that are all discussed by the Rishonim and Acharonim, such as:

• A non-Cohen within the Temple
• A Cohen outside of the Temple but for the sake of the Sacrificial Service
• Something holy but outside the Temple, such as we saw on the previous dafs regarding a Sefer Torah that needs to be carried to safety in a carmelis domain on Shabbos
• A Cohen inside the Temple but for a non-sacrifical part of the service
• Is this leniency limited to rabbinic restrictions on Sabbath laws (since the service generally overrides Sabbath laws anyhow) or is this leniency applied to all rabbinic laws

The basic precept that a priest within the holy site will be more careful, can be extrapolated or not within all the above scenarios and depend on how universal or how limited this provision is.  Some learn a hint for this concept from a verse in Zecharia 3:7 (see Chomas Anakh of the Chida ibid)

כֹּה־אָמַ֞ר יְהוָ֣ה צְבָא֗וֹת אִם־בִּדְרָכַ֤י תֵּלֵךְ֙ וְאִ֣ם אֶת־מִשְׁמַרְתִּ֣י תִשְׁמֹ֔ר וְגַם־אַתָּה֙ תָּדִ֣ין אֶת־בֵּיתִ֔י וְגַ֖ם תִּשְׁמֹ֣ר אֶת־חֲצֵרָ֑י וְנָתַתִּ֤י לְךָ֙ מַהְלְכִ֔ים בֵּ֥ין הָעֹמְדִ֖ים הָאֵֽלֶּה׃

“Thus said the LORD of Hosts: If you walk in My paths and keep My charge, you in turn will rule My House and guard My courts, and I will permit you to move about among these attendants.

• אִם־בִּדְרָכַ֤י תֵּלֵךְ֙ is the Torah law
• וְאִ֣ם אֶת־מִשְׁמַרְתִּ֣י תִשְׁמֹ֔ר the rabbinic prohibitions
• גַם־אַתָּה֙ תָּדִ֣ין אֶת־בֵּיתִ֔י וְגַ֖ם תִּשְׁמֹ֣ר אֶת־חֲצֵרָ֑י regarding “My House”, e.g., the Temple, only the actual law (Din) is required, not more.

While we are discussing this verse, there is a relevant Ramchal (Derech Etz Chayyim 56) that supplements this idea.  Ramchal says that the Torah ultimately could not remain with the angels and was given to man, because Angels do not grow and do not change.  This is what is referred to by the verse נָתַתִּ֤י לְךָ֙ מַהְלְכִ֔ים בֵּ֥ין הָעֹמְדִ֖ים הָאֵֽלֶּה. The Torah requires dynamic Interaction, and the use of judgment as it varies in circumstances.  This is precisely the reason why the Torah left room for rabbinic enactments, empowering the rabbis to create certain safeguards but also to allow for them not to apply in all situations.  A perfect example of this is the laws of Muktzah - objects we do not carry or move on Shabbos.  At a different time, perhaps Jews recognized the sanctity of Shabbos and had an intuitive and intrinsic reluctance to handle objects that were not holy for Shabbos. At that time, they did not need rabbis to tell them to abstain from holding and handling certain objects. Only in later times, as sensitivity to the sanctity of the Sabbath became diluted, then being neede formal restrictions to tell them not to handle these objects.

והנה זאת התורה אשר נתאוו בה המלאכים, באמרם (תהלים ח ב): "תנה הודך על השמים" - על הקבלה אמרו, כי אין לומר על פשט התורה, וכי לא ידעו שאין שייך בהם פשטי התורה כמו שהשיב להם משה? ואף על פי כן לא נתן הקדוש ברוך הוא להם אלא לישראל. וכל כך למה? רק שיודע הקדוש ברוך הוא, שעסק הלימוד זה, הוא ראש לכל התיקונים, והתיקון אינו יכול להיות על ידי המלאכים, כמו שהארכנו בפרקים הקודמים, מחמת שאינם בעלי בחירה, רק המה כמוכרחים, אשר בשביל זה כתיב (זכריה ג ז): "ונתתי לך מהלכים בין העומדים האלה", ונקראים המלאכים "עומדים", מאחר שהם עומדים תמיד במדריגה אחת. אבל בני האדם המה בעלי בחירה, להם ישתנה התיקון על ידי עסק התורה, ולכן ניתנה התורה לישראל דוקא, שעל ידה יהיו נתקנים התיקונים האלה:

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