Audio by Dr. Michael Sokolow

[If one has] two [separate] kabs [of dough] from one of which Hallah had been taken separately, and from the other [too,] separately, and he went back [to them] and made [of] them one dough, R. Akiba declares it exempt, but the Sages declare it liable. [Thus] it is found that [the very proposition giving rise to] the stringency of the one [ruling] is [the proposition that gives rise to] the leniency of the other [ruling]. מ חלה 4.5
שני קבים שניטלה חלתן של זה בפני עצמו ושל זה בפני עצמו, וחזר ועשאן עיסה אחת-- רבי עקיבה פוטר, וחכמים מחייבין; נמצא חומרו קולו
A man may take the requisite amount for Hallah out of a [clean] dough from which Hallah has not [previously] been taken [his purpose being] to effect it in cleanness by way of going on separating [Hallah] therefrom in respect of [unclean] Demai, until it putrifies, since Hallah in respect of Demai may be taken from clean [dough] in respect of unclean [dough], and from [one dough in respect of another dough] which is not close together.  מ חלה 4.6
נוטל אדם כדי חלה מעיסה שלא הורמה חלתה, לעשותה בטהרה, להיות מפריש עליה והולך חלת דמאי, עד שתסרח  שחלת דמאי ניטלת מן הטהור על הטמא, ושלא מן המוקף

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