Augustine, Confessions §aug_conf_10_043: There is another evil of the day, which I would were sufficient for it.

There is another evil of the day, which I would were sufficient for it. For by eating and drinking we repair the daily decays of our body, until Thou destroy both belly and meat, when Thou shalt slay my emptiness with a wonderful fulness, and clothe this incorruptible with an eternal incorruption. But now the necessity is sweet unto me, against which sweetness I fight, that I be not taken captive; and carry on a daily war by fastings; often bringing my body into subjection; and my pains are removed by pleasure. For hunger and thirst are in a manner pains; they burn and kill like a fever, unless the medicine of nourishments come to our aid. Which since it is at hand through the consolations of Thy gifts, with which land, and water, and air serve our weakness, our calamity is termed gratification.