Chagigah 26B

שלא תגעו בשלחן.

that you not touch the table of the showbread. If you defile it by touching it, it would need to be removed for immersion, and this would lead to the temporary suspension of the mitzva of the showbread, which had to be on the table at all times.

כל הכלים שהיו במקדש יש להם שניים ושלישים, שאם נטמאו הראשונים ⁠— יביאו שניים תחתיהן. כל הכלים שהיו במקדש טעונין טבילה, חוץ ממזבח הזהב ומזבח הנחשת מפני שהן כקרקע, דברי רבי אליעזר, וחכמים אומרים: מפני שהן מצופין.

The Mishnah continues: All the vessels that were in the Temple had second and third substitute vessels, so that if the first ones became impure they could bring the second ones in their place. All the vessels that were in the Temple required immersion after the Festival, apart from the golden altar and the bronze altar, because they are considered like the ground and therefore, like land itself, not susceptible to impurity. This is the statement of R' Eliezer. And the Rabbis say: It is because they are coated.

גמ׳ תנא: הזהרו שמא תגעו בשולחן ובמנורה. ותנא דידן, מאי טעמא לא תני מנורה? שלחן כתיב ביה ״תמיד״, מנורה לא כתיב בה ״תמיד״.

Talmud: A tanna taught in a baraita that they would say to the am ha’aretz priests: Be careful lest you touch the table, as explained above, or the candelabrum, as the Talmud will explain. The Talmud asks: And regarding the tanna of our Mishnah, what is the reason he did not teach that they were instructed not to touch the candelabrum as well? The Talmud answers: With regard to the table it is written: “showbread before Me always” (Exodus 25:30), indicating that the table holding the showbread must always be in its place, whereas with regard to the candelabrum it is not written “always,” and therefore it can be removed for immersing.

ואידך: כיון דכתיב: ״ואת המנורה נכח השלחן״, כמאן דכתיב בה ״תמיד״ דמי. ואידך: ההוא לקבוע לה מקום הוא דאתא.

The Talmud asks: And regarding the other tanna, in the baraita, why does he include the candelabrum? The Talmud answers: Since it is written: “And you should set the table without the veil and the candelabrum opposite the table” (Exodus 26:35), indicating that the candelabrum must always be placed opposite the table; it is as though it is written “always” with regard to the candelabrum as well. And the other tanna, in the Mishnah, who does not object to removing the candelabrum for immersion, would reply: That verse comes only to establish a place for the candelabrum, to describe where it must be positioned, but it does not mean to say that it must be opposite the table at all times.