"As the Father hath sent me, I also send you." (John, XX, 21) The elucidation of the concept of mission, and of its implications, essentially pertains to the theologian. Nevertheless it is perhaps not irrelevant for a philosopher to offer some reflections of his own on the matter. For missionary activity, taken in its deeper meaning, forces our minds back to great basic metaphysical truths.
It is a primary principle in metaphysics that the good is coextensive with being and that the good tends by nature to diffuse and communicate. Bonum est diffusivum sui. To be or not to be means to abound in being or to shrink to nothingness. Thus it is that, at every level of existence, God loveth a cheerful giver (Eccli. XXXV, 77; St. Paul, II Cor., IX, 7). In this ontologic generosity of the act through which things triumph over nothingness we have the very first philosophical truth implied by missionary activity. Being is not avaricious, it demands to act and communicate, it demands to superabound.
Now it is when it comes to the realm of the spirit that this law of the basic generosity of being takes on all its force and significance. Then it means that truth, which is the life of the spirit, must be poured out and manifested. In order to be perfect it is enough for the intellect to know. But to be perfect is not enough; it is necessary to go beyond one's own perfection, and to perfect others. The intellect does not stop at its own perfection. Once perfected by truth, it abounds, it speaks, it utters this same truth through which it is perfected, and which must be made known to other intellects.
Truth must be spoken out. Truth must be manifested in the world. When the Gospel states: "Nothing is covered that shall not be revealed: nor hid, that shall not be known. That which I tell you in the dark, speak ye in the light," (Matth., X, 26-27) it is a lofty supernatural mystery of grace and redemption, but it is also a basic natural mystery of the condition of the spirit which is thus divinely expressed. I think that what is at the core of missionary activity, before any particular result or effect of the latter, even the most essentially needed, is this fundamental requirement by virtue of which everything hidden must be brought to light -- and, especially, the word of God, heard in the dark (in the inmost recess of a man's heart), must be uttered and witnessed to in the light. Father de Foucauld did not convert one single soul during the hot long years of solitude in the Sahara desert. Yet he made manifest the truth of the Cross, and he exercised in actual fact the most powerful, the most successful missionary activity. Now we are contemplating the fruits of this burning silent predication.
There is still another point upon which a Christian philosopher may lay stress. It deals with the mystery of the Church, who is the mystical body of Christ. We know that even among those who are "sitting in the shadow of death", souls in good faith, who are ignorant of the Gospel good tidings, may invisibly belong to the Church and be saved by the blood of Christ. Why, then, is it necessary to send missionaries to them? It is necessary, of course, in order to make the ways to the true God broader and easier, and to provide those men with the full riches of the means of salvation. Yes, but there is a still deeper reason. What is implied in the calling of mankind to salvation is the fact that for men the final end is to be saved, -- and that nevertheless to be saved is not enough, they must cooperate in the salvation of others, they must enter actively into the workings of the mystical body, which are a participation in the redeeming work of Christ, they must "fill up those things that are wanting of the sufferings of Christ" (as to the application, not as to the merit), "in [their] flesh, for His body, which is the Church" (St. Paul, Colos., I., 24) And they can do so only when they share in the sacramental life and the sacramental graces of the Church, when they have been made by baptism active members of the Church, co-workers in His mystical body. Then not only can they be redeemed, but -- through the Body as a whole to which they belong in this full and active sense, and in whose task and sufferings they are actively engaged -- they can also participate in the redeeming work of the Savior.
I think that in the last analysis it is to this supreme end, to this supreme purpose, that the necessity for having missionaries sent all over the world points. And here we are confronted with a final and supreme application of this basic law of superabundance and generosity, inscribed in the very structure of being, which I stressed in this paper.