In an encyclical issued this Ascension Day, Pope John Paul II calls ecumenism, the search for Christian unity, "a duty of the Christian conscience enlightened by faith and guided by love." An encyclical letter is the most authoritative form of papal message. This is the 12th such letter of John Paul's 17 years as pope.

Here John Paul reproaches those commentators who have maintained for a decade that he is cool to ecumenism, saying that promoting Christian unity must pervade all that the church does.

John Paul recalls that Pope John XXIII, in summoning the Second Vatican Council, associated the internal reform of the Roman Catholic Church with ecumenical openness and says that "at the Second Vatican Council the Catholic Church committed herself irrevocably to following the path of the ecumenical venture."

Does this letter mean that ecumenism will become a priority of the final part of this pontificate, leading to the fulfillment in some way of the pope's dream that Christianity will be reunited by the year 2000? Certainly this pope now asserts a particular responsibility to promote unity among Christians because of the Roman See's claim to be the successor of St. Peter. This is in keeping with a direct line of papal encyclicals, stretching back to Pius IX in 1848, which for the most part have been one-way appeals to separated Christians to reunite with Rome.

What is new in l995 is that in this letter John Paul II admits that he must heed calls "to find a way of exercising the primacy which, while in no way renouncing what is essential to its mission, is nonetheless open to a new situation."

At the end of the 115-page document John Paul states that "the new situation" could mean sharing some of the pope's authority with national bishops' conferences. Such a shift would be welcomed by Episcopalians who have expressed reluctance to enter into full communion with a church in which the primate exercises the right of "immediate, ordinary jurisdiction" over local dioceses. "Immediate, ordinary jurisdiction" means the authority of a primate to intervene in the affairs of a diocese, even over the opposition of a local bishop.

Is this pope actually willing to reform his office? At least he acknowledges in this encyclical that the exercise of "immediate, ordinary jurisdiction" constitutes a difficulty for most other Christians "whose memory is marked by certain painful recollections." Episcopalians would agree with this.

In the encyclical the pope reviews some of the high points of the 17 years of his pontificate. Episcopalians will be pleased when he writes that with "profound emotion I remember praying together with the Primate of the Anglican Communion at Canterbury Cathedral (May 29, 1982); in that magnificent edifice, I saw an eloquent witness both to our long years of common inheritance and to the sad years of division that followed."

The pope's encyclical requests, in the strongest terms, that Roman Catholic diocesan bishops grasp leadership once again of the flagging ecumenical movement. John Paul II has put his finger on a point where the ecumenical problem lies in this country - with the Roman Catholic bishops.

In the United States in the last decade many bishops of the Roman obedience have created the impression that ecumenism is of very low priority. They are unable to fit ecumenical events into their busy schedules, ecumenical conferences are cancelled, ecumenical budgets slashed and ecumenical officers removed, clergy and religious at times quietly discouraged from ecumenical participation.

The decline is so apparent that one international Anglican leader said recently that the impression is given that we are in "the twilight of ecumenism." John Paul has perceived this, wishes to halt it, and has directed the bishops - most of whom he himself has appointed - to do so.

Yet there is disappointment. There is a nostalgic quality to the encyclical. The pope looks back to the heady days of Vatican II, but neglects the complex developments of recent years in the areas of gender and sexuality. He writes as though the theological clock had stopped in 1965. The encyclical fails to record the revolutionary joint progress of the ARCIC process which has led to so much Anglican-Roman Catholic agreement on the sacrament of the Eucharist that the Vatican's ecumenical council could write last summer that our differences over the Eucharist are so minimal, they require "no further study at this time."

Similarly, the encyclical fails to record the full weight of the most recent critical scholarship which would support the Roman Catholic recognition of the validity of Anglican ministry. At a recent international conference on Anglican orders at the General Theological Seminary [TLC, May 14], not a single Roman Catholic expert would defend Apostolicae curae, papal letter which declared Anglican orders "null and void" in 1896. And yet this discredited statement is still an operative document of the Roman Catholic Church.

In short, the papal vision must now be translated into the necessary concrete theological and practical ventures, for example, the abrogation of Apostolicae curae, which will make this bold initiative a credible reality at the dawn of a new millennium. Any incisive effort to reclaim a Christian basis for social analysis and for cultural plentitude cannot proceed in isolation from greater Christian unity. Where such unity is attained, Christ is present in the human fellowships.

Dr. Franklin, professor of church history at the General Theological Seminary, is on the Standing Committee on Ecumenical Relations.