Reference for Yoma 147:9

הכי נמי מסתברא דאי סלקא דעתך דאורייתא כוי ספיקא הוא איצטריך קרא לאתויי ספיקא אי משום הא לא איריא קסברי

[To turn to] the main text: As for the matter of less than the legal minimum, R'Johanan said: It is forbidden by Biblical law, whilst Resh Lakish said: It is permitted by Biblical law. R'Johanan said, It is forbidden by Biblical law; since it could be joined [to form a minimum] it is forbidden food that he is eating. Resh Lakish said: It is permitted by Biblical law, for the Divine Law speaks of eating and this is not [eating].<span class="x" onmousemove="('comment',' Since below the minimum it may be nibbling, but it is eating that is forbidden.');">¹⁵</span> - R'Johanan raised the following objection against Resh Lakish: I know only that whatsoever involves punishment is subject to a prohibition; but in the case of the koy,<span class="x" onmousemove="('comment',' A kind of bearded deer or antelope (Jast.) . It is left undecided as to whether it belongs to the genus of cattle, the tallow of which is forbidden, or to beasts of chase, the tallow of which is permitted.');">¹⁶</span> and what is less than the legal minimum, since they do not involve punishment, I might say that they are not subject to a prohibition either, therefore the text reads: No fat.<span class="x" onmousemove="('comment',' Lev. VII, 23. This proves that less than a legal minimum is prohibited by the Torah.');">¹⁷</span> - This is only Rabbinical and the text [adduced] is but a mere support. And that is also logical. For if one should assume that the prohibition is Biblical, surely [the status of] the koy is doubtful and no Scriptural text is necessary to cover a doubtful<span class="x" onmousemove="('comment',' Since there is no doubt before the Divine Lawgiver, no Scriptural text would be necessary to cover a doubtful situation.');">¹⁸</span> case! - Were it only for this there would be no argument, they would hold

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