FD 0 GUARDING THE DEPOSIT OF FAITH IS THE MISSION WHICH THE LORD ENTRUSTED TO HIS CHURCH, and which she fulfills in every age. The Second Vatican Ecumenical Council, which was opened 30 years ago by my predecessor Pope John XXIII, of happy memory, had as its intention and purpose to highlight the Church’s apostolic and pastoral mission, and by making the truth of the Gospel shine forth to lead all people to seek and receive Christ’s love which surpasses all knowledge (cf. Eph 3:19).
The principal task entrusted to the Council by Pope John XXIII was to guard and present better the precious deposit of Christian doctrine in order to make it more accessible to the Christian faithful and to all people of good will. For this reason the Council was not first of all to condemn the errors of the time, but above all to strive calmly to show the strength and beauty of the doctrine of the faith. “Illumined by the light of this Council”, the Pope said, “the Church.. . will become greater in spiritual riches and gaining the strength of new energies therefrom, she will look to the future without fear.. . Our duty is to dedicate ourselves with an earnest will and without fear to that work which our era demands of us, thus pursuing the path which the Church has followed for 20 centuries.”1
With the help of God, the Council Fathers in four years of work were able to produce a considerable number of doctrinal statements and pastoral norms which were presented to the whole Church. There the Pastors and Christian faithful find directives for that “renewal of thought, action, practices and moral virtue, of joy and hope, which was the very purpose of the Council”.2
After its conclusion, the Council did not cease to inspire the Church’s life. In 1985 I was able to assert, “For me, then – who had the special grace of participating in it and actively collaborating in its development – Vatican II has always been, and especially during these years of my Pontificate, the constant reference point of my every pastoral action, in the conscious commitment to implement its directives concretely and faithfully at the level of each Church and the whole Church.”3
In this spirit, on 25 January 1985, I convoked an extraordinary assembly of the Synod of Bishops for the 20th anniversary of the close of the Council. The purpose of this assembly was to celebrate the graces and spiritual fruits of Vatican II, to study its teaching in greater depth in order that all the Christian faithful might better adhere to it, and to promote knowledge and application of it.
On that occasion the Synod Fathers stated: “Very many have expressed the desire that a catechism or compendium of all Catholic doctrine regarding both faith and morals be composed, that it might be, as it were, a point of reference for the catechisms or compendiums that are prepared in various regions. The presentation of doctrine must be biblical and liturgical. It must be sound doctrine suited to the present life of Christians.”4 After the Synod ended, I made this desire my own, considering it as “fully responding to a real need of the universal Church and of the particular Churches”.5
For this reason we thank the Lord whole-heartedly on this day when we can offer the entire Church this “reference text” entitled the Catechism of the Catholic Church, for a catechesis renewed at the living sources of the faith!
Following the renewal of the Liturgy and the new codification of the canon law of the Latin Church and that of the Oriental Catholic Churches, this catechism will make a very important contribution to that work of renewing the whole life of the Church, as desired and begun by the Second Vatican Council.

1 John XXIII, Discourse at the Opening of the Second Vatican Ecumenical Council, 11 October 1962: AAS 54 (1962), 788-91.
2 Paul VI, Discourse at the Closing of the Second Vatican Ecumenical Council, 7 December 1965: AAS 58 (1966), 7-8.
3 John Paul II, Discourse of 25 January 1985: L’Osservatore Romano, 27 January 1985.
4 Final Report of the Extraordinary Synod of Bishops, 7 December 1985: the Enchiridion Vaticanum vol. 9, II B a, n. 4:p. 1758, n. 1797.
5 John Paul II, Discourse at the of Closing of Extraordinary Synod of Bishops, 7 December 1985, n. 6: AAS 78 (1986), 435.