15 Finally, these recommendations also apply to seminarians and priests. You should expend even greater effort on them that they may be worthy of the priesthood and that they may manifest virtue fitting the times. For this reason, the sacred seminaries justly claim the greater part of your attention. Direct them in the best way possible and provide them with all that is necessary so that through the dedication of selected teachers, seminarians will be trained in the morals and virtues required by their order and, moreover, in all the beauty and glory of doctrine, both human and divine.
Source: Constanti Hungarorum (Vatican.va)