Reference for Pesachim 235:11

אמר ר"א בן עזריה קשין נקביו של אדם כיום המיתה וכקריעת ים סוף שנאמר (ישעיהו נא, יד) מהר צועה להפתח וכתיב בתרי' רוגע הים ויהמו גליו

R'Eleazar B''Azariah said: A man's excretory organs [when blocked up] are as painful as the day of death and [as difficult to overcome]<span class="x" onmousemove="('comment',' The Heb. has both meanings.');">²³</span> as the dividing of the Red Sea, for it is said, The prisoner hasteneth to be loosed; [and he shall not go down dying into the pit, neither shall his bread fail];<span class="x" onmousemove="('comment',' Isa. LI, 14.');">²⁴</span> and that is followed by [For I am the Lord thy God,] who stirreth tip the sea, that the waves thereof roar.<span class="x" onmousemove="('comment',' Ibid. 15. This is understood as an allusion to the dividing of the Red Sea.');">²⁵</span>

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