Reference for Yoma 149:8

בשלמא למאן דאמר דגים אבל עריות לא פריצי בהו היינו דכתב (שיר השירים ד, יב) גן נעול אחותי כלה [גו'] אלא למ"ד עריות מאי מעין חתום מהנך דאסירין לא פריצי בהו

What does 'for nought' mean according to him who says they were real fish? - They were brought to them from public property, for a Master taught: When the Israelites were drawing water, the Holy One, blessed be He, prepared for them in the water little fish for their pitchers. According to him who said 'real fish', but with regard to illi intercourse [he holds] they were not dissolute, it will be quite right that Scripture said: A garden shut up is my sister, etc.<span class="x" onmousemove="('comment',' Cant. IV, 12.');">¹⁴</span> but according to the view that fishes mean 'illicit intercourse', what 'fountain sealed' is her - They were not dissolute with regard to forbidden relations.<span class="x" onmousemove="('comment',' [I.e., those that had been already forbidden to the sons of Noah, v. Sanh. 57b].');">¹⁵</span>

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