Fruits of the Ginosar

Talmud Brochot 44a

The Babylonian Talmud discusses the fruits of Ginosar in Mesechta Brochot 44a.

The story is as follows: The rav ate the fruits until the flies slipped from his forhead from the sweat. Superficially, this can be seen as a way of showing how flavorful the fruits were that even a great rav could not restrain himself from over indulging in them.
But Maimonides teaches us that many strange stories in the Talmud should be understood metaphorically (as a mashal). This story can be understood as a mashal in the following way.

The Fly is a symbol of the yetzer HaRa (gemara) and the sweat refers to the sin of Adam which resulted in our working by our sweat. Sin in general comes from our involvment if the physical. But this rav was on such a high level that his physical inclinations (gashmiut) were not affected by "the fly".

The fruit of the ginosar are like the fruits of Gan Eden (gemara) and so the zadikim will enjoy them. I.e they will exist in this world unaffected by the yetzer hara. The punishment of Adam was that he would eat bread by his sweat, i.e. his gashmiut will come to him in a way which will taint him with the yetzer hara. But this rav got his bread without that sin.

Thus the Gemara here says that these fruit are not batel to bread, but bread it batel to them. They represent this higher, sinless involvment with the physical, different from Adam's involvment with the physical. He produced bread by the sweat of his brow. Thus his bread represents the sinfull existence.
Also Yaakov avinu is compared to Adam before the sin (gemara).

Taken from what I heard from Rav Kaminetsky