Reference for Pesachim 60:2

אמר ליה רבינא לרב אשי וכי מאחר דאיתותב רבא בר אהילאי אמאי קאמר רב קדירות בפסח ישברו אמר ליה התם תנור של מתכת הכא בקדיר' של חרס

Rabina said to R'Ashi: Now since Raba B'Ahilai was refuted, why did Rab say, Pots must be broken on Passover?<span class="x" onmousemove="('comment',' For we see that greased ovens (these were generally of earth) can be reheated and then used, the heat expelling the traces of fat. Then let the pots too be subjected to fire, which would likewise expel the absorbed leaven.');">¹</span> - There it was a metal oven, replied he, [whereas] here an earthen pot [is referred to]. Alternatively, both refer to earthenware: this [the oven] is fired from the inside;<span class="x" onmousemove="('comment',' Which is efficacious to expel absorbed matter.');">²</span>

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