Reference for Eruvin 53:12
וחד מתני אמעשר לא שנו אלא מים בפני עצמו ומלח בפני עצמו דאין ניקחין אבל מים ומלח ניקחין בכסף מעשר
He who applied [the limitation]<span class="x" onmousemove="('comment',' 'Was taught only in respect' etc.');"><sup>29</sup></span> to tithe [applies it] with more reason to 'erub.<span class="x" onmousemove="('comment',' The restrictions on the kinds of food permitted are more stringent in respect of the second tithe than in that of 'erub; and, since salt water is itn permitted in the case of the former, there can be no question that it is permitted in that on the latter. V. Tosaf. s.v. a.l.');"><sup>30</sup></span> He, however, who applied it to 'erub does not apply it<span class="x" onmousemove="('comment',' Lit., 'but . . not'.');"><sup>31</sup></span> to tithe.