Zevachim 191

אלא קדירות של מקדש אמאי (אמר רחמנא) ישברו נהדרינהו לכבשונות א"ר זירא לפי שאין עושין כבשונות בירושלים

Then why should the pots in the Temple be broken: let them be returned to the kiln?<span class="x" onmousemove="('comment',' Which would expel what they had absorbed.');">¹</span> - Said R'Zera: Because kilns are not permitted in Jerusalem.<span class="x" onmousemove="('comment',' On account of the smoke.');">²</span>

אמר אביי וכי עושין אשפתות בעזרה אישתמיטתיה הא דתני שמעיה בקלנבו שברי כלי חרס נבלעין במקומן

Abaye retorted: And are then refuse heaps permitted in the Temple court?<span class="x" onmousemove="('comment',' Sc. of broken potsherds.');">³</span> [Abaye, however,] had overlooked what Shemaiah of Kalnebo<span class="x" onmousemove="('comment',' Kar-nebo, 'the city of Nebo', conjectured to be Borsippa, Funk, Monumenta, I, p. 299.');">⁴</span>

אלא הא דאמר רב נחמן אמר רבה בר אבוה תנור של מקדש של מתכת הוה נעביד דחרס דהסיקו מבפנים הוא

recited: The fragments of earthen vessels were swallowed up in their place.<span class="x" onmousemove="('comment',' Yoma 21a.');">⁵</span> Now, when R'Nahman said in Rabbah B'Abbuha's name, 'The Temple oven was of metal',let it be an earthen one, since It was heated within?<span class="x" onmousemove="('comment',' And thus what it absorbed of the sacrifices would be expelled.');">⁶</span>

דכיון דאיכא שתי הלחם ולחם הפנים דאפייתן בתנור וקדושתן בתנור הוה ליה כלי שרת וכלי שרת דחרס לא עבדינן

- Since the Two Loaves and the Shewbread<span class="x" onmousemove="('comment',' V. Lev. XXIII, 15-17; Ex. XXV, 30.');">⁷</span> were baked in the oven and were sanctified in the oven, it became a service vessel, and we do not make earthen service vessels.<span class="x" onmousemove="('comment',' Offerings such as meal-offerings, loaves etc. were sanctified by being placed in service vessels. The Two Loaves and the Shewbread, however, were not placed in a service vessel, but were kneaded and shaped outside the Temple court, then brought in and baked in the oven. Thus the oven itself sanctified them, and ipso facto ranked as a service vessel.');">⁸</span>