Reference for Eruvin 33:10

לימא רב הונא דאמר כר' יהודה ורבי יצחק דאמר כר' יוסי

One maintains that Sabbath is the determining factor<span class="x" onmousemove="('comment',' The extent of the area permitted is dependent on the number of persons alive at the moment Sabbath began. If at that time the three were alive the survivors may continue to use the full area throughout the Sabbath even according to R. Judah. If, however, two persons only were present when the Sabbath began and they enclosed an area larger than two beth se'ah they are, according to R. Judah, forbidden its use even if their number had been augmented during the Sabbath.');">²⁰</span> and the other maintains that the determining factor is [the number of actual] tenants.<span class="x" onmousemove="('comment',' If an area larger than two beth se'ah had been enclosed its use is permitted if the number of tenants was three, though when the Sabbath began it was only two, and forbidden if the number was two though it was three when the Sabbath began.');">²¹</span> You may conclude that it is R'Huna who held that the determining factor was the Sabbath.

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