Philo Judaeus De Agricultura 97

[97] But, in the allegorical explanations of these statements, all that bears a fabulous appearance is got rid of in a moment, and the truth is discovered in a most evident manner.

The serpent, then, which appeared to the woman, that is to life depending on the outward senses and on the flesh, we pronounce to have been pleasure, crawling forward with an indirect motion, full of innumerable wiles, unable to raise itself up, ever cast down on the ground, creeping only upon the good things of the earth, seeking lurking places in the body, burying itself in each of the outward senses as in pits or caverns, a plotter against man, designing destruction to a being better than itself, eager to kill with its poisonous but painless bite. But the brazen serpent, made by Moses, we explain as being the disposition opposite to pleasure, namely, patient endurance, on which account it is that he is represented as having made it of brass, which is a very strong material.