Reference for Shabbat 42:3

וכבתה אין זקוק לה ורמינהו מצותה משתשקע החמה עד שתכלה רגל מן השוק מאי לאו דאי כבתה הדר מדליק לה לא דאי לא אדליק מדליק וא"נ לשיעורה:

I would have learnt this dictum originally. But he learnt it [now]? — The difference is in respect of the studies of one's youth.<span class="x" onmousemove="('comment',' These are more abiding. Abaye felt that he would have had a surer hold upon it had he learned it earlier. ');">⁵</span> Now, if it goes out, does it not require attention? But the following contradicts it: Its observance is from sunset until there is no wayfarer in<span class="x" onmousemove="('comment',' Lit., 'Until the foot ceases from'. ');">⁶</span>

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