Avodah Zara 55: G-d's Jealousy, Benefitting from Other's Foolishness

Why isn’t G-d jealous of idols?  Another parable is used to explain this concept: When a man takes a second wife, his first wife is only jealous if the second wife is less distinguished that she.  She is not jealous of a second wife who is more distinguished than she, and she is not angry at her husband.

The Gemara asks why people come back from idol worship with their bodies healed.  Two parables are offered to explain this occurrence.  One man was trusted by everyone to hold their belongings without proper witnesses present.  One man did not trust him and brought witnesses to his transaction.  Later he did not require witnesses for a second agreement.  His wife suggested that they make demands.  The man replied that he should not benefit from this trusted man’s foolishness.

A new Mishna teaches that we are permitted to buy a winepress from a Gentile even though the grapes have gone through the machine and the Gentile’s hands touched the grapes in the winepress and puts them into the vat to be trodden upon.   The grape juice only takes on the status of ‘wine’ once it is in the vat.  Only that wine is prohibited.  Stepping on the grapes together with Gentiles is permitted.  Harvesting is not permitted by some of the rabbis.  It is permitted by Rav Huna.   Similarly, a baker who is in a state of ritual impurity cannot knead or arrange bread, and others are not permitted to do so beside him.  However, it is permitted to carry the bread with him to the bread seller.

The Gemara takes note the details of winemaking and the reasons that rabbis belive that wine or juice might be permitted at different points in the process.  They quote a baraita that reinterprets a mnemonic so that it reflects a more stringent ruling.  That means that a Jew who is paid to tread on grapes with a Gentile is benefitting from a prohibited action.