מכשירין ה׳Makhshirin 5

Mishnah 1א׳

מִי שֶׁטָּבַל בַּנָּהָר, וְהָיָה לְפָנָיו נָהָר אַחֵר וְעָבַר בּוֹ, טִהֲרוּ שְׁנִיִּים אֶת הָרִאשׁוֹנִים. דָּחָהוּ חֲבֵרוֹ לְשָׁכְרוֹ, וְכֵן לִבְהֶמְתּוֹ, טִהֲרוּ שְׁנִיִּים אֶת הָרִאשׁוֹנִים. וְאִם כִּמְשַׂחֵק עִמּוֹ, הֲרֵי זֶה בְכִי יֻתַּן:

[If] one immersed in a river and [then] there was another river in front of him and he passed through it, the second [river's water] purifies the first [river's water, that is neither water will subsequently make food susceptible to impurity]. If his drunk friend pushed him or his animal [into the river after they had immersed], the second [water] purifies the first. And if [he pushed him] in jest that achieves BeKhi Yutan [a state where liquid put upon food makes it susceptible to impurity].

Mishnah 2ב׳

הַשָּׁט עַל פְּנֵי הַמַּיִם, הַנִּתָּזִין, אֵינָן בְּכִי יֻתַּן. וְאִם נִתְכַּוֵּן לְהַתִּיז עַל חֲבֵרוֹ, הֲרֵי זֶה בְכִי יֻתַּן. הָעוֹשֶׂה צִפּוֹר בַּמַּיִם, הַנִּתָּזִין וְאֶת שֶׁבָּהּ, אֵינָן בְּכִי יֻתַּן:

[If] one is swimming in the water that which splashes out does not achieve BeKhi Yutan. But if he intended to splash his friend, that does achieve BeKhi Yutan. [If] one makes bubbles in the water that which splashes and what is in it do not achieve BeKhi Yutan.