Reference for Taanit 56:11

בטל התמיד גמרא:

and it is further written, And Moses entered into the midst of the cloud, and went up into the mount; and Moses was in the mount forty days and forty nights.<span class="x" onmousemove="('comment',' Ibid. 18.');">¹⁵</span> The [remaining] twenty-four days of Sivan and the sixteen days of Tammuz make altogether forty. On the seventeenth of Tammuz he came down [from the mountain] and shattered the Tables, as it is written, And it came to pass as soon as he came nigh unto the camp, that he saw the calf.

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