Today’s Catechism sections discuss the missionary activity of the Church. Supporting material comes from the decree, “Ad Gentes”.

852 Missionary paths. The Holy Spirit is the protagonist, "the principal agent of the whole of the Church's mission."345 It is he who leads the Church on her missionary paths. "This mission continues and, in the course of history, unfolds the mission of Christ, who was sent to evangelize the poor; so the Church, urged on by the Spirit of Christ, must walk the road Christ himself walked, a way of poverty and obedience, of service and self-sacrifice even to death, a death from which he emerged victorious by his resurrection."346 So it is that "the blood of martyrs is the seed of Christians."347

853 On her pilgrimage, the Church has also experienced the "discrepancy existing between the message she proclaims and the human weakness of those to whom the Gospel has been entrusted."348 Only by taking the "way of penance and renewal," the "narrow way of the cross," can the People of God extend Christ's reign.349 For "just as Christ carried out the work of redemption in poverty and oppression, so the Church is called to follow the same path if she is to communicate the fruits of salvation to men."350

854 By her very mission, "the Church . . . travels the same journey as all humanity and shares the same earthly lot with the world: she is to be a leaven and, as it were, the soul of human society in its renewal by Christ and transformation into the family of God."351Missionary endeavor requires patience. It begins with the proclamation of the Gospel to peoples and groups who do not yet believe in Christ,352 continues with the establishment of Christian communities that are "a sign of God's presence in the world,"353 and leads to the foundation of local churches.354 It must involve a process of inculturation if the Gospel is to take flesh in each people's culture.355 There will be times of defeat. "With regard to individuals, groups, and peoples it is only by degrees that [the Church] touches and penetrates them and so receives them into a fullness which is Catholic."356

855 The Church's mission stimulates efforts towards Christian unity.357 Indeed, "divisions among Christians prevent the Church from realizing in practice the fullness of catholicity proper to her in those of her sons who, though joined to her by Baptism, are yet separated from full communion with her. Furthermore, the Church herself finds it more difficult to express in actual life her full catholicity in all its aspects."358

856 The missionary task implies a respectful dialogue with those who do not yet accept the Gospel.359 Believers can profit from this dialogue by learning to appreciate better "those elements of truth and grace which are found among peoples, and which are, as it were, a secret presence of God."360 They proclaim the Good News to those who do not know it, in order to consolidate, complete, and raise up the truth and the goodness that God has distributed among men and nations, and to purify them from error and evil "for the glory of God, the confusion of the demon, and the happiness of man."361

The decree, “Ad Gentes”, explains the missionary task of the Church:

9. And so the time for missionary activity extends between the first coming of the Lord and the second, in which latter the Church will be gathered from the four winds like a harvest into the kingdom of God.(23) For the Gospel must be preached to all nations before the Lord shall come (cf. Mark 13:10).

Missionary activity is nothing else and nothing less than an epiphany, or a manifesting of God's decree, and its fulfillment in the world and in world history, in the course of which God, by means of mission, manifestly works out the history of salvation. By the preaching of the word and by the celebration of the sacraments, the center and summit of which is the most holy Eucharist, He brings about the presence of Christ, the author of salvation. But whatever truth and grace are to be found among the nations, as a sort of secret presence of God, He frees from all taint of evil and restores to Christ its maker, who overthrows the devil's domain and wards off the manifold malice of vice. And so, whatever good is found to be sown in the hearts and minds of men, or in the rites and cultures peculiar to various peoples, not only is not lost, but is healed, uplifted, and perfected for the glory of God, the shame of the demon, and the bliss of men.(24) Thus, missionary activity tends toward eschatological fullness.(25) For by it the people of God is increased to that measure and time which the Father has fixed in His power(cf. Acts 1:7). To this people it was said in prophecy: "Enlarge the space for your tent, and spread out your tent cloths unsparingly" (Is. 54:2).(26) By missionary activity, the mystical body grows to the mature measure of the fullness of Christ (cf. Eph. 4:13); and the spiritual temple, where God is adored in spirit and in truth (cf. John 4:23), grows and is built up upon the foundation of the Apostles and prophets, Christ Jesus Himself being the supreme corner stone (Eph. 2:20).

Footnotes

345 John Paul II, RMiss 21.
346 AG 5.
347 Tertullian, Apol. 50, 13: PL 1, 603.
348 GS 43 # 6.
349 LG 8 # 3; 15; AG 1 # 3; cf. RMiss 12-20.
350 LG 8 # 3.
351 GS 40 # 2.
352 Cf. RMiss 42 47.
353 AG 15 # 1.
354 Cf. RMiss 48-49.
355 Cf. RMiss 52-54.
356 AG 6 # 2.
357 Cf. RMiss 50.
358 UR 4 # 8.
359 Cf. RMiss 55.
360 AG 9.
361 AG 9.