9 It seems to Us that the Divine Master Himself is repeating to everyone those words of consolation and exhortation: "Lift up your eyes and see the countries; for they are white already to harvest." But since the number of missionaries is inadequate for present needs, the following words are in a way the counterpart of that invitation: "The harvest indeed is great, but the laborers are few. Pray ye therefore the Lord of the harvest that he send forth laborers into his harvest."
Source: Evangelii Praecones (Vatican.va)