Every thing that are forbidden by the Torah for eating,
even though it is permitted to benefit (from it),
if it is something that is specifically for eating,
it is forbidden to do business with it,
or to use it as collateral.1
Even to buy it (in order) to feed
one's non-Jewish worker, is forbidden.
However, something which is not intended for eating,
for example horses or donkeys,
one is allowed to trade with them.
(Non-kosher) fat is also permitted for trade,
for it is said:2
''It can be used for for any (other) purpose.''1) For example by borrowing or lending money or goods and using this item as the collateral - security deposit.
2) Lev. 7:24.
כל דבר שאסור מן התורה באכילה
אף על פי שמותר בהנאה
אם הוא דבר המיוחד למאכל
אסור לעשות בו סחורה
או להלוותו עליו
ואפילו לקנותו להאכילו
לפועלו אינו יהודי אסור
אבל דבר שאינו עומד לאכילה
כגון סוסים וחמורים
מותר לעשות בהם סחורה
וחלב גם כן מותר בסחורה
שהרי נאמר
בו יעשה לכל מלאכה If there came to a person by chance a forbidden item,
for example he was fishing
and there came up in his net an unclean fish,
and similarly there came to him
an animal that is suffering from illness or was attacked1 in his home,
it is permitted to sell it since he did not intend that this (would happen).
He needs to sell it immediately and not wait
until (after) he has fattened it up by him.
He can also sell them by (using) an (Jewish) agent,
even if the agent makes some profit from this.
However, the agent can not buy it (for himself),
because if he did this is (considered) as trading (with it).1) One can only eat a meat from a kosher, healthy animal that was ritually slaughtered. If the animal is suffering from some sickness that may cause it to die - it is termed nevila - or was attacked by a predator leaving it with injuries that it will not recover from - it is termed terefah ''torn''. In both cases the animal is no longer considered kosher as food.
אם נזדמן לאדם באקראי דבר אסור
כגון שצד דגים
ועלה במצודתו דג טמא
וכן מי שנזדמנה לו
נבלה וטרפה בביתו
מותר למכרם כיון שלא נתכוין לכך
וצריך למכרו מיד ולא ימתין
עד שתהא שמנה אצלו
ויכול למכרם גם על ידי שליח
אף על פי שהשליח ירויח בו
אבל לא שיקנה השליח לחלוטין
דאם כן הוי אצלו סחורה Similarly, it is allowed to take as payment aginst a debt,
non-kosher items and sell them immediately,
because it is forbidden to keep them,
in order to make some money on them.
However, one may keep them
in order not to lose their original value. וכן מותר לגבות בחובו
דברים טמאים וימכרם מיד
דאסור להשהותן
כדי להשתכר בהם
אבל מותר להשהותן
בכדי שלא יפסיד מן הקרן Something which is only forbidden by the Rabbis,
such as non-Jewish cheese,
may be traded in. דבר שאין איסורו אלא מדרבנן
כגון גבינות של נכרי
מותר לעשות בהן סחורה