We come now to chapter 5 of Tractate Avodah Zarah, Mishnah 1. As we have already established, yayin nesech - wine that was used for idolatrous purposes - is forbidden to derive any benefit from, meaning that one may not gain any economic advantage from it. A person may not drink the wine, and he may not sell it or trade it and profit from it either. That is the law from the Torah.
The Sages added a decree of their own: even when it is not known that a particular item was actually used for idolatrous purposes, it is at the very least stam yeinam, and that too is forbidden to benefit from by rabbinic law.
Furthermore, it is not only direct benefit, through drinking or selling, that was forbidden, but indirect benefit as well - providing ancillary services and earning money in connection with that wine. For example, the logistics work, the mere transporting of the wine from place to place, and receiving wages as a carrier or a courier - that too is forbidden by rabbinic law. This prohibition applies not only to actual yayin nesech, but also to stam yeinam, any wine belonging to gentiles, because of the stringency the Sages adopted regarding yayin nesech in general. It emerges, then, that one may not do business with yayin nesech or with any other wine belonging to idolaters, and not even as a hired employee as opposed to an owner. Our task in this Mishnah is to explore the details of these laws.
"HaSocher es haPo'el la'asos imo b'yayin nesech":
The Mishnah opens: "HaSocher es haPo'el la'asos imo b'yayin nesech" - one who hires a worker to work for him with yayin nesech, his wages are forbidden. The owner is a gentile, the wine in his possession is at the very least stam yeinam or worse, and he hires a Jew to perform some task for him, such as moving the wine from place to place. If the Jew receives payment for clearing the yayin nesech out of the storeroom, his wages are forbidden and he may not benefit from them. And if he has already received them, he must dispose of them.
"Secharo la'asos imo melachah acheres":
On the other hand, if the owner of the wine hired the Jew for a different task, such as removing from the storeroom the empty barrels that are not full of wine, "af al pi she'amar lo ha'aver li chavis shel yayin nesech mimakom l'makom" - even though he said to him, "Move this barrel of yayin nesech for me from place to place," meaning that the gentile said to him: since you are already at it, there is also a barrel of wine there that belongs to me, move that one too - his wages are permitted.
And here is the explanation of the case: when it is possible to separate the payment for the work that does not involve yayin nesech from the payment for the work that does involve yayin nesech, the worker may keep the wages he received for the permitted work. For example: he receives one dollar for moving each barrel. Ninety-nine barrels are empty and one is full of wine, and at the end of the day he will receive one hundred dollars for his work. The Mishnah teaches that he may keep ninety-nine of them. Either he refuses to accept the one dollar, or, if he received all one hundred, he must take one dollar and throw it into the Dead Sea, so that he does not benefit from that dollar he received in exchange for the work he did with yayin nesech.
Wages that are contingent on the entire job:
All of this is based on the assumption that the payment he receives for the permitted work can be separated from the payment for the forbidden work with the yayin nesech. But the opposite case is where the gentile says: "This room is full of barrels, I will give you one hundred dollars to take them all out." If it turns out that one of the barrels contains yayin nesech, the Jew may not accept payment for this job at all, since receiving the hundred dollars is contingent on moving that barrel of yayin nesech, and it turns out to be as though the payment were given for that very barrel. For if he were to clear out only ninety-nine barrels and leave one behind, the owner would say: "I am not paying you anything, because the job was to empty the storeroom, and you did not do it." From here we see that everything depends on that last barrel, and it turns out that he is receiving payment for it - and therefore he may not keep any part of the wages, not even ninety-nine percent of them. That is the first part of the Mishnah.
"HaSocher es haChamor l'havi aleha yayin nesech":
The second part of the Mishnah presents a similar idea: "HaSocher es haChamor l'havi aleha yayin nesech" - one who rents out a donkey to carry yayin nesech on it, its rental fee is forbidden. A Jew owns a donkey, and the gentile wishes to rent it in order to transport his wine on it: renting out the donkey is like hiring himself out for the transport work, and therefore the entire rental fee he receives for it is forbidden, and he may not keep it, for exactly the same reason. There is no great novelty in this.
The novelty lies in the second half of the Mishnah: "secharah leisheiv aleha" - the gentile says: I need the donkey in order to ride on it.
This rider will presumably bring along his bottle of wine together with the rest of his food, and that too will be loaded onto the donkey. Is there a problem with this? May the owner of the donkey accept payment for renting it out, even though the gentile will almost certainly transport wine of libation on it as well?
The answer is that it is permitted: "af al pi shehiniach ha'oved kochavim lagino aleha - secharah mutar" - even though the gentile places his lagin on the donkey, a wine vessel larger than a cup, something like a wine bottle, this makes no difference, and the entire rental fee is permitted.
The reason is as follows: suppose the gentile were to say to the owner of the donkey, "I said I would pay you a hundred dollars to rent your donkey, but in fact I am not going to be carrying a bottle of wine with me. Can I get a discount?" The owner would answer him, "What are you talking about? Why would I give you a discount? This has nothing to do with whether or not you place the bottle of wine on the donkey, that is not the point at all." The Gemara, and likewise Tosafos, prove from here that no part of the payment given to the owner of the donkey is for transporting wine of libation, and therefore the entire rental fee is permitted.
In summary: in this Mishnah we learned that the prohibition of deriving benefit from wine of libation and from ordinary gentile wine extends also to indirect earnings connected with the wine. One who hires a worker to work with him on wine of libation - his wage is forbidden; but one who hires him for other work that can be separated out, even if he was incidentally asked to move a barrel of wine - his wage is permitted, except for the payment for that particular task, which he must cast into the Dead Sea. But when the entire wage is contingent upon completing all the work, including the barrel of wine, the whole wage is forbidden. So too with renting out a donkey: if he rented it out to carry wine of libation on it - the rental fee is forbidden; if he rented it out merely for riding - the rental fee is permitted, even if the gentile placed his lagin on it, since the rental fee is in no way given in exchange for transporting the wine.