14 Moreover your vigilance for your priests must be great and even singular, so that the smaller the number of workers, the greater their zeal in cultivating the vineyard of the Lord. The words of the Gospel, the harvest is indeed great, seem to apply literally to you, since the people of Portugal have always loved religious instruction; they receive it eagerly when they perceive in the priests, their teachers, the embellishments of virtue and the reputation for learning. It is marvelous how fruitful the future work of the clergy will be in instructing the people, but especially the youth, when that work is crowned with dignity and zeal. Good example is the best means of cultivating in men the love of virtue. For this reason let all priests take care not only that nothing is noted in them which is at variance with their office and the rules of their state, but also that the holiness of their lives and morals may shine forth, like a Lamp on a lampstand, giving Light to all in the house.
Source: Pergrata (Vatican.va)