Reference for Pesachim 115:4

מתיב רבא בערבי פסחים נשחט בשבע ומחצה וקרב בשמונה ומחצה בין בחול בין בשבת ואי סלקא דעתך בשמונה ומחצה דאורייתא היכי מקדמינן ליה

and one hour for its preparation.<span class="x" onmousemove="('comment',' Thus the 'two evenings' are from midday (= six) until eight and a half hours, and from nine and a half hours until nightfall (= twelve) .');">⁹</span> Raba objected: ON THE EVE OF PASSOVER IT IS SLAUGHTERED AT SEVEN AND A HALF HOURS AND OFFERED AT EIGHT AND A HALF HOURS, WHETHER IT IS A WEEKDAY OR THE SABBATH. Now if you think that [it must be slaughtered] at eight and a half hours according to Scriptural law, how may we perform it earlier?

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