יורה דעה קי״טYoreh De'ah 119

Se’if 1א׳

הֶחָשׁוּד לֶאֱכֹל דְּבָרִים הָאֲסוּרִים, בֵּין אִם הוּא חָשׁוּד בְּאִסוּר תּוֹרָה בֵּין אִם הוּא חָשׁוּד בְּאִסוּר דְּרַבָּנָן, אֵין לִסְמֹךְ עָלָיו בָּהֶם; וְאִם נִתְאָרַח עִמּוֹ, לֹא יֹאכַל מִשֶּׁלוֹ מִדְּבָרִים שֶׁהוּא חָשׁוּד עֲלֵיהֶם. הַגָּה: וְיֵשׁ אוֹמְרִים אֲפִלּוּ מִמִּי שֶׁאֵינוֹ חָשׁוּד, רַק שֶׁאֵין מַכִּירִין אוֹתוֹ שֶׁהוּא מֻחְזָק בְּכַשְׁרוּת, אָסוּר לִקְנוֹת מִמֶּנּוּ יַיִן אוֹ שְׁאָר דְּבָרִים שֶׁיֵּשׁ לָחוּשׁ לְאִסּוּר. מִיהוּ אִם נִתְאָרַח אֶצְלוֹ, אוֹכֵל עִמּוֹ (בֵּית יוֹסֵף בְּשֵׁם הַרַמְבַּ"ם פי"א דמ"א ופ"ג דִּין כ"א).

A Jew who is suspected of eating forbidden things, whether he is suspected of something forbidden by the Torah or something forbidden by the rabbis, one may not rely on his word. And if one is a house-guest with him, he may not eat from his foods for which he is suspected. Rema: And there are those who say that even for someone who is not suspected, but rather that we merely do not know him to be established regarding keeping kosher, it is forbidden to buy from him wine or other things for which there is a concern about prohibited items. In any case, if one is a house-guest with him, he may eat with him.

Se’if 2ב׳

אִם אֵינוֹ חָשׁוּד לֶאֱכֹל דְּבָרִים אֲסוּרִים, אֲבָל הוּא חָשׁוּד לְמָכְרָם, מִתְאָרֵחַ אֶצְלוֹ וְאוֹכֵל עִמּוֹ. וְכֵן אִם שׁוֹלֵחַ לְבֵיתוֹ, מֻתָּר, דַּחֲזָקָה שֶׁמַּה שֶּׁהוּא אוֹכֵל מְשַׁגֵּר לוֹ. עוֹבֵר עֲבֵרָה לְתֵאָבוֹן, לֹא מִקְרֵי חָשׁוּד (בֵּית יוֹסֵף בְּשֵׁם הָרַשְׁבָּ"א).

If one is not suspected to eat forbidden things, but is suspected to sell them, one whom is a house-guest by him may eat with him. And thus if he sends food to your house, it is permitted, because it is presumed that he would not eat something strange to him, and someone who succumbs to temptation is not considered suspect.

Se’if 3ג׳

מֻתָּר לִתֵּן מִשֶּׁלוֹ לְחָשׁוּד לֶאֱכֹל דְּבָרִים הָאֲסוּרִים, כְּדֵי שֶׁיְּתַקֵּן אוֹ יְבַשֵּׁל לוֹ, וְלֹא חַיְשִׁינָן שֶׁמָּא יַחֲלִיפֶנּוּ, כֵּיוָן שֶּׁאֵינוֹ חָשׁוּד עַל הַגֶּזֶל. וְאִם נוֹתֵן לְמִי שֶׁחוֹשֵׁשׁ בְּתַקָּנָתוֹ, וְהוּא חָשׁוּד לֶאֱכֹל דְּבָרִים הָאֲסוּרִים, אָסוּר, שֶׁמָּא יִתְקַלְקֵל מַה שֶּׁנּוֹתֵן לוֹ וְיַחֲלִיפֶנּוּ בְּשֶׁלּוֹ. כֵּיצַד, הֲרֵי שֶׁנָּתַן לַחֲמוֹתוֹ הַחֲשׁוּדָה עַל הָאִסוּר, אָסוּר, שֶׁבּוֹשָׁה מֵחֲתָנָהּ וְרוֹצָה בְּתַקָּנַת בִּתָּהּ וּלְפִיכָךְ מַחְלֶפֶת לוֹ רַע בְּטוֹב. וְכֵן הַנּוֹתֵן לְפֻנְדָּקִית הַחֲשׁוּדָה, פְּעָמִים שֶׁבּוֹשָׁה מֵהָאַכְסְנַאי וּמַחְלֶפֶת לוֹ רַע בְּטוֹב. וּמִכָּל מָקוֹם מֻתָּר לְהַפְקִיד אֶצְלוֹ וְשֶׁיַּחֲזִיר לוֹ הַדְּבָרִים כְּמוֹ שֶׁהִפְקִידוּ אֶצְלוֹ.

One may give his food to the one who is suspected of eating non-kosher items in order that he should fix or cook them, and there is no concern that he will switch them, since he is not suspected of outright robbery. And if it is given to someone who is zealous about his actions, and he is suspected of eating non-kosher, it is forbidden, as perhaps he will damage what he was given and then switch it out with his own food. How? If one gives something to his father in law who is suspected regarding forbidden things, it is forbidden, because of the shame of marriage, and he wants to make his daughter look good, and therefore he will switch out something bad with something good. And thus if one gives something to an innkeeper who is suspect, sometimes he is embarrassed of his guest and will switch something bad for something good. (And in any case, it is permitted to deposit items with him and they should be in the same state as when they were deposited).