11 We wish especially to exhort the bishops and clergy of the new Christian communities to pray to God, and to conduct themselves in such a way that the priestly gift they are enjoying may grow in spiritual fruitfulness; in their talks with the people, as often as feasible they should praise the dignity, the beauty, and the merits of the priesthood, and, by so doing, they will induce all those whom God has chosen for this exalted honor to respond to the call with an open and generous heart. They should also cause the faithful entrusted to their care to pray to God for this cause, in unity of spirit with the whole Church, which, in response to the Divine Redeemer's exhortations, prays "the Lord of the Harvest to send forth laborers into his harvest," (18) especially at the present time, when "the harvest indeed is great, but the laborers are few."(19)
Source: Princeps Pastorum (Vatican.va)