פירוש על עבודה זרה 30:5

Ashi says that what really matters is whether we can make a reasonable assumption that the item sold will be used to transgress a commandment. It is reasonable to assume that one might decide to slaughter a cow instead of using it for work. This would not be reasonable when it comes to a donkey. It is unlikely that one will use plowing instruments for anything else. Therefore they cannot be sold to one who does not observe the laws of the sabbatical year.
We should note how R. Ashi reverts to simple reason to support R. Huna’s actions. Rabbah on the other hand wanted to find an authoritative source. This may reflect a general shift from tradition as a source of authenticity to logic.