According to the Mishna (30b) if a non-Jew lent money to a Jewish person before Pesaḥ, and held the Jew’s hametz as collateral, the Jew would be allowed to pay back the loan after the holiday and make use of the hametz. Conversely, if the Jew lent money to the non-Jew and held the non-Jew’s hametz as collateral over Pesaḥ, that hametz could not be used after the holiday is over.
A baraita is quoted on our daf that brings in another opinion. According to Rabbi Meir, if the Jew is holding a non-Jew’s hametz over Pesaḥ as collateral on a loan, it cannot be used after Pesaḥ, but there is another opinion in the baraita that rules that the hametz can be used.
Our Gemara explains that these cases are specifically when the collateral – in this case, the hametz – is actually handed over to the lender, who takes possession of it. The idea that collateral becomes the possession of the lender is based on a statement by Rabbi Yitzhak, who explains the passage (Devarim 24:13) which teaches how a lender must return the collateral given to him by a poor person to him when he needs it. According to the pasuk, when the lender fulfills his Biblical obligation and returns the collateral, he is credited with tzedaka – charity. Rabbi Yitzhak asks – why should he be credited with charity, if the object remains the property of the poor person? We must conclude that ba’al hov koneh mashkon – that the lender takes actual ownership of the collateral. The disagreement between the tannaim is based on a dispute as to whether the same rules of ownership transfer apply when dealing with non-Jews.
The Talmud presents a wide variety of methods for transferring ownership of objects. Purchase by means of money is, perhaps, the best known; other methods include meshikha – pulling an object, hagbahah – lifting an object, halipin – a symbolic method to indicate agreement, and others. The Gemara does not make clear whether these methods are Rabbinic in origin and normal money purchase is the most basic method, or, perhaps, these are the fundamental methods of transfer, and purchase with money is a weaker method – one that indicates agreement, but does not affect the transfer in and of itself.
The appropriate method of transferring ownership between Jews and non-Jews is a topic that is discussed several times in the Talmud. In our case, the lack of clarity with regard to the power of these different methods is the source for the discussion in the Gemara about how a Jew and non-Jew can successfully buy and sell hametz from one-another.