Reference for Pesachim 54:11
אמרו לו נבילה תוכיח שאסורה באכילה ואינה טעונה שריפה אמר להן הפרש נותר אסור באכילה ובהנאה וחמץ אסור באכילה ובהנאה מה נותר טעון שריפה אף חמץ טעון שריפה
R'JUDAH SAID: THERE IS NO REMOVAL etc. It was taught, R'Judah said: There is no removal of leaven save by burning, and logic impels this: if nothar, which is not subject to 'there shall not be seen' and 'there shall not be found', requires burning, then leaven, which is subject to 'there shall not be seen' and 'there shall not be found', how much the more does it require burning! Said they to him: Every argument that you argue [which] in the first place is stringent yet in the end leads to leniency is not a [valid] argument: [for] he did not find wood for burning, shall he sit and do nothing, whereas the Torah ordered, Ye shall put away leaven out of your houses,<span class="x" onmousemove="('comment',' Ex.XII, 15.');"><sup>16</sup></span> [which means] with anything wherewith you can put it away?