Halakhah for Pesachim 141:7
מתיב רבא ההלל והשמחה שמנה ואי אמרת בעינן זביחה בשעת שמחה הא זמנין סגיאין דלא משכחת לה אלא שבעה כגון שחל י"ט הראשון להיות בשבת א"ר הונא בריה דרב יהודה משמחו בשעירי הרגלים
R. Kahana said: How do we know that the emurin of the hagigah of the fifteenth are disqualified through being kept overnight? Because it is said, neither shall the fat of My feast [haggi] remain all night until morning; and in proximity thereto 'the first' [is stated], to intimate that this 'morning' means the first morning. To this R. Joseph demurred: [Thus] the reason is that 'first is written, but if 'first' were not written I would say, what does 'morning' mean? the second morning; [but] is there a case where the flesh is disqualified from the evening, whereas the emurim [are fit] until morning? Said Abaye to him, Yet why not? Surely there is the paschal offering according to R. Eleazar b. 'Azariah, where the flesh is disqualified from midnight, whereas the emurim [are fit] until morning? - Said Raba, This is R. Joseph's difficulty: is there a case where the Tanna does not require 'first' in respect of the flesh, whereas R. Kahana requires 'first' in respect of the emurim? What is this [allusion]? - For it was taught: Neither shall any of the flesh which thou sacrificest the first day at even, remain all night until the morning: <br>