My first book, published as long ago as 1942, was called "The Nature of Catholicity". Its truculent youthful anti-catholicism has been made out of date by the remarkable changes which have since taken place in Rome but I should want to stand by its positive argument. Ubi Christus ibi ecclesia. The catholicity of the church is to be found where there is faithfulness to the apostolic testimony to Christ. Because that testimony insists that Christ is not to be identified with the church, faithfulness finds expression in self-criticism. A "structure of catholicism" is discernible but it cannot be conveyed by historical succession alone because it points the church away from itself to Christ and makes clear why historical discontinuity is sometimes unavoidable because the church has always to be open to reformation by the living word.

In speaking of catholicity now, however, I should want to place the emphasis differently. Catholicity has to be discovered more in relation to the church's present calling and future destiny than to her historical origins and traditions. If the essence of the church lies in her faithfulness to the apostolic testimony, her fullness is to be discovered as she grows into maturity, a maturity which is never more than partially realized on this earth. Catholicity, therefore, is always more a matter of aspiration than of achievement. It should find expression through appropriate liturgy, ministry, tradition and corporate life but these must strengthen the church's vigilance, her ability to watch and pray and effectively to discern the signs of the times.

Reformed churches frequently say that they are pilgrims, seeking a city whose foundations are not yet visible. The implications of this are that the light illuminating the path and many of the signposts indicating the direction of the pilgrimage are determined not by their historical starting-point but by their destination.

This does not banish the necessity to discuss catholicity with reference to the traditional notes or marks of the church, holiness, apostolicity and unity, but these have to be considered in relation to the growth of the Christian community towards maturity, "measured by nothing less than the full stature of Christ" (Eph 4.13). What that stature is we only know fitfully and imperfectly. The gifts of ministry are provided to discover and grow into it, and to overcome the innumerable difficulties which lie in the way. It is not the self-confidence derived from a long institutional pedigree but the sense of direction and independence of judgement which come from the Spirit which enable the church to avoid being "tossed to and fro" by secular trends and instead "to build itself up in love" (Eph 4.14-16). This means that no church can ever enjoy the securitas which comes from the automatic possession of catholic status.

A church aspiring to catholicity will always strive to maintain a balance between the elements of memory and hope. It is through memory that she discovers the basis of her apostolicity, holiness and unity. Apostolicity derives from faithfulness to the apostolic testimony in Scripture and from the effort to fulfil the apostolic commission to proclaim the gospel ecumenically. It is from this apostolicity that the church's holiness arises, in the sense of having a distinctive, separated vocation to live as in but not of the world. She quickly loses her way unless her memory is constantly refreshed by return to its biblical sources. Her unity must also be linked with memory. This must be understood to refer to the church's experience of the guidance of the Holy Spirit throughout the ages as well as to her corporate life as a visible community at the present time. The ministry of the word and sacrament exists not only to enable a particular church give heed to the apostolic testimony but also to pay due attention to the witness of tradition, placing no limits to that witness which are narrower than those set by the Spirit. Only thus can any particular church hope to become, in PT Forsyth's phrase "the outcrop of the great church", and not a provincial sect.

Yet this act of recollection will be inappropriately selective, and also probably distorted and self-justifying, unless it is influenced by the fact that the church has also to look forward, although that forward look in its turn must be taken only when the act of recollection has been made. Just as the latter helps the church see the direction in which to move, so what she sees lying ahead should help in interpretation of her history. This then becomes an aid to self-criticism rather than a temptation to rewrite history to suit present convenience. Hindsight may sometimes make it possible to see where our forebears went wrong but, so far from evoking the pride in being up-to-date which comes readily to the self-consciously radical, it is a reminder of how easily mistakes are made, especially when one is consumed by a zeal for righteousness. The more honest a church's struggles are to discover our Lord's present will, the humbler and more discriminating her attitude to the past is likely to become. Thus, Reformed churches can gratefully acknowledge how much they owe to Calvin and other Reformers and how much they can learn from them in an age with very different assumptions. At the same time their very study of them will make them see that undue attention to the letter of their teaching does no service to their memory because it inhibits their own freedom to discern fresh possibilities for the future.

Two examples illustrate how maintaining the balance between memory and hope can affect decisions in important areas of life today.

The first refers to relations between men and women. Well-known biblical passages, reinforced by traditional teaching and practice, have led many people to believe that Christian faith is committed to male primacy and female subordination as a divine ordinance, although they may also want to say that these are to be interpreted in the light of the Christian understanding of the mutuality of service. Even Barth, who has an extremely positive view of the relationship, chose to expound it chiefly in terms of the second creation story in Genesis. It is true that Christians may need to avoid being "tossed to and fro" by militant secular feminism and by current sexual laxity and regressiveness. They may still need to give weight to Genesis and the Pastoral Epistles and the traditional teaching of particular churches. At the same time, because this relationship is so fundamental, the Christian doctrines of reconciliation and redemption lead to the expectation that its future nature should be determined more by hope than by memory, more by what we shall be moving towards than by what we have inherited. If growth to maturity in Christ is our goal, and in him there is neither male or female, then relations between men and women should increasingly reflect the equality in dignity, the shared responsibility and the mutual consideration and support of the heirs of the kingdom rather than any hierarchical order of primacy and subordination. This should be true in marriage, in secular vocations and, not least, in the ministry of the word and sacrament. Such an attitude is more genuinely catholic than any which pays more attention to practice in the past than to our common destiny.

The other example comes from current discussions about reunion, which clearly reflect the complexity of the relation between memory and hope. The modern ecumenical movement was produced by a kindling of hope which stimulated the memory to rediscover the church of the New Testament as, in intention, a worldwide community called to transform all parts of life in the light of the coming kingdom. It evoked discontent not only with the divisions but also with the provincialism, and the related immaturity, of existing churches. This issued in a commitment to work for reformation. It is significant that several early ecumenists were Reformed theologians who emphasized the tension between the coming kingdom and empirical churches. They saw the ecumenical movement as essentially a step towards catholicity, in our sense of growth towards maturity, with memory and hope held in balance. They used the word "ecumenical" rather than "catholic" because of the latter word's obvious associations with some particular churches. Two factors have appeared, however, which create complications.

First, those churches which make an exclusive claim to the name "catholic" will normally discuss Christian reunion only with reference to the adjustment of other forms of church order to their own, which they regard as normative. In practice, this means endless discussions between Catholics and Protestants about the status of the sacramental ministry and its relation to historic catholic forms. This prevents both from enquiring with sufficient thoroughness whether they may have a common calling for the future, one which might conceivably lead them to conclude that over some matters of historic debate they can safely leave the dead to bury their dead.

Secondly, even in discussion of reunion between churches with a common Protestant heritage, the participants seem to find it difficult to do more than to try to integrate their existing church structures. These, however, arose to meet past needs and, in particular, reflect the great expansion of denominational secretariats in recent times. Schemes of reunion even among Protestants tend to become little more than realignments of denominational service agencies rather than attempts to clarify the basic "structure of catholicism" in order that the churches can be better equipped for moving ahead. The effort involved in doing even this often diverts limited energies from more fundamental tasks of reformation. Thus, well-intentioned movements towards reunion can actually hinder rather than promote growth towards maturity.

This is not necessarily an argument against such movements but it is a warning that the cause of ecumenism is not to be identified with efforts to reunite existing denominational structures. These need to be submitted to ecumenical scrutiny collectively as well as individually and, in so far as they do no more than enshrine irrelevant memories, may need to be by-passed rather than integrated with one another. Fresh thought needs to be given to what the relation between partially divided, partially cooperative churches should be if room is to be made for creative growth. Institutional reunion on current assumptions may not always provide the answer.

Some possible lines of thought are already clear. One is that, as Jacques Ellul insists, Christian renewal is more likely to come from below than from above, from unexpected and unofficial sources rather than from "the properly constituted authorities". This is not because any special virtues attach to weakness, irresponsibility and inexperience, as current Christian romanticism sometimes implies. It is because the proper exercise of authority leaves little room for originality. Those with authority run the risk of becoming corrupted by power but, even if they escape this, most of their energies have to go into maintenance work rather than into pioneering. Again, this is not necessarily to disparage those in authority. More can be said in defence of Bishop Mynster than Kierkegaard allowed. The fact remains that those in authority demonstrate their grasp of what catholicity means as much by their acceptance of the limitations of their function as by the way in which they exercise it. Above all people, they will know how hard it is for institutions as for individuals to be born again when they are old and they will be vigilant to protect their institutions against the temptations that inevitably come with old age. This means resisting rather than encouraging the institutional tendency to centralize power and not being unduly disturbed when churches have untidy edges, since such untidiness is often the necessary corollary of growth. They will be particularly vigilant to check the development of clericalism because strong clerical corporations drain vitality from other parts of the body. Realism will teach them that no church is likely to retain the form of a servant for long without frequent purges of officious clerics.

This implies that the marks of catholicity as they relate to the ministry of the word and sacrament are likely to be the opposite of those which churches which lay claim to exclusive catholicity hold to be essential. Heavily centralized administrations, especially those with imposing figureheads to whom are ascribed semi-divine powers, rigid hierarchies, sharply-defined boundaries, elaborate legal arrangements and built-in defences against possibilities of change are likely to be a sign of arrested development rather than of growth towards maturity. Churches aspiring to catholicity should have flexible structures and they should be as decentralized as is compatible with a worldwide mission and the need to maintain institutional integrity against concentrations of secular power, especially nation-states with their predilection for making totalitarian claims. Their officers should be primarily theologians and pastors rather than administrators, personally unobtrusive and adept both at self-criticism and at encouraging the self-criticism of the institutions which they serve. If the church's aspiration to catholicity is to have any credibility as a pointer to the fullness of life promised for all mankind, the way in which she handles power without corruption in her internal life should provide both challenge and encouragement to those who have to exercise it in the other institutions of society.

It will be clear from this that, although renewal is more likely to come from below than from above, it is no part of our argument that ecclesiastical structures should only be small-scale, with a bias towards the experimental and the tentative. On the contrary, such an attitude would confirm churches in a merely marginal role in human affairs. We live in a large-scale, interdependent, highly industrialized world, one which members of Reformed churches, for good or for ill, have done a great deal to help bring into being. Although magnificent work was done in the last generation by Barth, Niebuhr and others, they have not yet received enough guidance from their pastors about how they are to find their way as pilgrims through this world to the coming kingdom. This is particularly true as it affects their actions in the spheres of politics, economic life, science, the arts, communications and leisure, which do so much to determine the shape of all our lives. This is what makes the theme of the Ottawa general council, "Thine is the kingdom, the power and the glory", so particularly timely. The way to catholicity lies more in this direction than through the continuance of the debate between rival clerical corporations about their relation to one another in the light of their historic claims. Conversations with churches which call themselves "Catholic", with their own distinctive memory on such matters, can be helpful in dealing with the Ottawa theme but we must be on our guard, in our proper eagerness to keep in contact with current semi-reformed Catholicism, against allowing its internal preoccupations to deflect us from discovering the possibly more radical demands of our own vocation. This is true both in relation to finding how the Reformed churches of European origin can be born again when they are old and to helping newer churches, linked with emerging social groups in other continents, to rise to the heights of their calling.