לֹֽא־תִשְׁחַ֥ט עַל־חָמֵ֖ץ דַּם־זִבְחִ֑י וְלֹא־יָלִ֣ין לַבֹּ֔קֶר זֶ֖בַח חַ֥ג הַפָּֽסַח׃
זאָלסט ניט מקריב זײַן מיט געזײַערטן ברױט דאָס בלוט פֿון מײַן שלאַכטאָפּפֿער, און דאָס שלאַכטאָפּפֿער פֿון דעם יָום-טובֿ פֿון פּסח זאָל ניט איבערנעכטיקן ביז אין דער פֿרי.
Mekhilta DeRabbi Yishmael
(Ibid. 15) "Only on the first day you shall eliminate leaven from your houses": before the eve of the festival. You say this, but perhaps (the meaning is) on the day of the festival itself? (This cannot be, for) it is written (Ibid. 34:25) "Do not slaughter with chametz the blood of My sacrifice" — Do not slaughter the Paschal lamb when chametz is still found, (whence it is derived that chametz is forbidden from the sixth hour on the fourteenth of Nissan [when the Paschal lamb is slaughtered]). These are the words of R. Yishmael.