Reference for Yoma 102:8

ורבי יהודה אמר לך פיתחא בדרום קאי ורבי מאיר כמאן סבירא ליה אי כרבי יהודה סבירא ליה ניעול כרבי יהודה אי כרבי יוסי סבירא ליה ניעול כר' יוסי

but in the Second Temple, because there was lacking the partition wall<span class="x" onmousemove="('comment',' I Kings VI, 16 refers to the two cedar-covered partitions, with a vacant space between then, which separated the Holy Place from the Holy of Holies, occupying the space of one cubit, but the text: And he built twenty cubits on the hinder part of the house with boards of cedar from the floor unto the joists, leaves it undecided from which of the two holy areas the space of one cubit was to be deducted.');">¹⁰</span> which had been in the first Temple - and the Sages were doubtful as to whether its sacredness partook of the character of the Holy or the Holy of Holies, they made two curtains.<span class="x" onmousemove="('comment',' In the second Temple that partition was replaced by two curtains with a space between them.');">¹¹</span>

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