XXX. (112) Very clearly therefore is the good man thus shown to be a farmer, and the bad man to be only a cultivator of the land; and I wish that while he is thus cultivating the land, the earthly nature which environs him, had imparted some vigour to him, and had not, as it has, taken away something of the power which he had before, for we read in the scripture, “It shall not add its strength to thee to give it to thee,” (113) and such would be the character of a man who was always eating or drinking and never satisfied, or who was incessantly indulging in the pleasures of the belly, and devoting his energies to the gratifying of his carnal appetites, for deficiency produces weakness, but fulness produces strength; but when, amid abundance of things an insatiability is united with excessive intemperance, that is hunger; and they are truly wretched whose bodies are filled, while their passions are empty and still thirsting; (114) but of the lovers of knowledge the prophet speaks in a great song, and says, “That she has made them to ascend upon the strength of the earth, and has fed them upon the produce of the Fields,”{36}{#de 32:13.} showing plainly that the godless man fails in attaining his object, in order that he may grieve the more while strength is not added to these operations in which he expends his energies, but while on the other hand it is take from them; but they who follow after virtue, placing it above all these things which are earthly and mortal, disregard their strength in their exceeding abundance, using God as the guide to conduct them in their ascent, who proffers to them the produce of the earth for their enjoyment and most profitable use, likening the virtues to fields, and the fruits of the virtues to the produce of the fields, according to the principles of their generation; for from prudence is derived prudent action, and from temperance temperate action, and from piety pious conduct, and from each of the other virtues is derived the energy in accordance with it.