SUMMARY This is an attempt to formulate the nature of the sacraments in relation to the Church, to the deposit of faith, and to church order, in order to try to establish a way of viewing sacramental practice in terms more positive than validity and invalidity, which now loom uncomfortably large over ecumenical relationships. Part I, dealing with three preliminary questions, first gives a survey of the pronouncements of the Church on the invalidity of Protestant sacraments; added to the defectus intentionis the Church denounces in the Protestant ministry a lack of competence to administer the sacraments after Baptism, even in the case of the Anglican Church, which claims a valid ministry. After this it is laid down that whereas the concept of (in)validity is only prominent in paradoxical situations (especially those in which mala fides plays a part), traditional theology has formulated the nature of the sacrament almost exclusively in terms of (in)validity, thus basing itself on a marginal concept of the sacraments instead of on their normal, fruitful celebration, in which the awareness of (in)validity is virtually absent. Finally, two current evaluations of Protestant sacraments are rejected as unsatisfactory. The first holds that Protestant sacraments celebrate salvation only spiritually, not really; this distinction is put aside as falsifying the nature of the sacrament as a sign, and the incarnatory character of grace. The second holds that a Protestant sacrament is a votum sacramenti; this is rejected because it puts the disposition outside the sacrament itself, unless the formula is understood to mean: a desire of the recognition of the sacrament, in which case it would be acceptable as a basis for discussion. Part II is entitled: The Role of Church and Church Doctrine. It is suggested that the development of ecclesiology under the influence of ecumenicism may provide a fresh background to current sacramental theology. Up to Mystici Corporis the Catholic view of reunion was largely retrospective and historical; it could only be conceived in terms of return, of a restoration of a lost unity. But the „concentric” view of the Church as well as the conception of the”people of God” have done much to make theologians aware of the provisional character of many structures in the Church, which in Mystici Corporis had been rather too massively identified with the eschatological Church itself. Thus, the essential unity of the Church has come to be viewed as Christ's eschatological gift to his people rather than as the institutional unity around the deposit of faith and church order. Thus, Church reunion has come to be viewed eschatologically and prospectively. Creeds and church orders are partial, provisional realizations of the Church of the eschaton, and if the Churches are not to suffer from sclerosis, they are continually to refer their teachings and regulations to the eschaton. If the Churches, in an ecumenical spirit, do not mutually condemn one another on the basis of these provisional realities, but recognize each other as Churches on the strength of their willingness to regauge creeds and church orders, (which willingness or obedience of faith, marks them as true Churches),—then they are no longer caught up in the mutual excommunications of the past. But since sacraments are acts of the Church, and real according as the Church that celebrates them is real, the question may be raised whether the sacramental celebrations of Protestant Churches cannot be called true sacraments.—This is applied to the question, whether the Protestant Churches are orthodox with regard to the sacraments. Faith and dogma, although forming one reality, are not identical. Dogma is essentially provisional and asks for continual revision and complement in order to approximate the fullness of faith. The basic condition for a true sacrament is the intentici faciendi quod facit Ecclesia, i.e. the fundamental act of faith. This act of faith is indeed judged by the standard of orthodoxy, but if the Churches are prepared to revise and complete their creeds, doctrinal differences would seem no longer to be indicative of defectus intentionis. This is not to say that Protestant sacraments are valid, since this would imply full recognition on the level of doctrine; but the essence of he sacrament is not in its validity, which is a consequence on the level of Church order rather than the basis of a true sacrament. Part III, entitled: The Competence of the Minister, sets out to state that the sacraments are not entirely tied up with the minister ordinarius. Not only can some sacraments in cases of emergency still be administered by extraordinary ministers, but all the sacraments have in the course of history been administered by ministri extraordinarii, whether canonically authorized or not. Mere canonical authorization, however, is not the source of the sacrament, since canon law, or church order, is merely a juridical formalization of the organic ordo caritatis; it is an advance recognition of the validity of a ministry which is basically authorized by the presence of Christ in the Church. In normal cases, anyone unauthorized who would venture to administer a sacrament would frustrate the celebration, not because he would be going against canon law, but because by going against canon law he would ex supposito go against the mind of the Church, and thus manifest defectus intentionis. In extraordinary circumstances, however, the law is suspended; and even though special canonical provisions have been made for cases of emergency, no lawgiver can ever hope to provide for all emergencies. It is suggested, therefore, that the canonical system of extraordinary ministers does not exhaust the possibilities. If sacraments are celebrated in good faith and praeter (not contra) ordinem on account of suspension of church order—and these conditions may well prevail in Protestant Churches—it is submitted that the question may be asked whether these are not true sacraments, although still in need of recognition, i.e. validity. Part IV (The Essence of the Sacrament of Order and its Canonical Shape) deals with the question, whether the Protestant ministry itself can be described in terms of the Sacrament of Order. As a preliminary step it is laid down that the Church (or the laity) and the ministry cannot be two entirely irreducible levels; both the New Testament and the tradition of the Church view the ministry as a diakonia to the Church, organically and authoritatively functioning in the community as a principle of order. A parallel is drawn between kerygma and dogma on the one hand, and Church and Ordo on the other; both pairs present a living structure, in which the latter of each pair acts as a principle of order to the former. The prototypical form of dogma is Scripture, the prototypical form of Ordo is the apostolic ministry; they were both recognized in the second century, in the canon of Scripture and in apostolic episcopacy respectively. Thus, apostolic succession is the principle of order of the apostolic tradition, which are no more two irreducible strains in the history of the Church than Ordo and Church. It is pointed out that defining Ordo and apostolic succession entirely in terms of service to Church and apostolic tradition does not degrade the authority of the hierarchy to a merely delegated one, since the Ordo sacramentally embodies and personifies ”ex sese” the corporate faith of the Church. With regard to apostolic succession in history (the”pipeline”), it is suggested that this is in the first place a succession in office: successio in locum Petri, in locum apostolorum. By this emphasis on locus the burden of church doctrine is brought to bear on the organic diakonia in the Church, after the prototype of the apostolic ministry in the primitive community. It is then submitted that the historical succession, in the form of episcopal consecration, first generally prescribed by the Council of Nicaea, is the canonical realization of the essential apostolic succession in office. In this hypothesis, failure to abide by the canonical concretization frustrates the Sacrament of Order, not by itself, but because ex supposito this is mala fides with respect to the diakonia and the unity of the Church. But it may be asked whether there is not a true Sacrament of Order in cases where the ministry in its formal,”diaconal” aspects is faithfully exercised, provided church order is along episcopal lines, even if praeter ordinem the ministry does not receive its office as a result of historical succesion. Finally, Part V, entitled Perspective with Reservations, tries to view the problem of communicatio in sacris as a necessary concomitant of ecumenicism. Ecumenicism, it is suggested, has caused a landslide in this problem. If traditional moral theology held communicatio in sacris sinful in itself, only to be condoned for special reasons, the ecumenical spirit requires it, even if for good, although regrettable, reasons full intercommunion or communion cannot as yet be achieved. For communicatio in sacris to be lawful some conditions must be fulfilled. Positively, there must be a measure of doctrinal agreement, at least to such an extent that differences in doctrine are covered by a clear awareness of the possibility of eventual agreement resulting from willingness to revise and complement established doctrine. Negatively, communicatio in sacris may not be intended as an act of disloyalty to one's own creed and church order; this requires in the individual participant an integration of established doctrine into a perceptive appreciation of the possibilities of doctrinal development, and avoidance of scandal. Communicatio in sacris cannot help straddling the fence; retrospectively it requires loyalty to, prospectively it is the fruit of an awareness of the provisional character of, creeds and church orders. Finally, it is pointed out that, since full unity will only be achieved in the eschaton, the unity of the Church in via will always be provisional, i.e. work along the lines of communion and even intercommunion of larger units in the Church. This means that the concept of sacramental validity as an expression of inter-church recognition will always be a necessary feature of sacramental practice.