These effects are incomparably more violent in the case of meat. It has an extremely fattening effect on the flesh, it causes a special corpulency, and heats
the blood. The
vapors and gases it produces are very oppressive to the brain. For this
reason it is not used at all by monks. It is the prerogative of people
living in the world who are always engaged in hard physical labor. But
even for them the constant use of meat is harmful.
"What!" at this point would-be wiseacres exclaim, "Meat is allowed man by God, and do you forbid its use?" To this we reply in the words of the Apostle, "All things are lawful for me, but not all things are helpful. All things are lawful for me, but not all things edify" (1 Cor. 10, 23). We decline from the use of meat not because we regard it as unclean but because it produces a special corpulence in our whole constitution and hinders spiritual progress.