It seems almost bizarre that some Christians who have spent many years urging politicians to sit and talk at one table should find themselves so embarrassed when brothers and sisters in Christ then assume that they themselves can eat at one table, the table of the Lord.

That Christians should make this assumption is a result not of carelessness, ignorance or indifference: it is rather that they have taken seriously the ecumenical journey about which church leaders speak.

For a long time there have been two distinct attitudes towards members of separated churches sharing together in Holy Communion. There has been the view that sharing together thus can be a means of bringing the separated churches to unity, and there has been the view that sharing in Holy Communion is a sign of unity that has already been achieved.

On the whole reformed churches have taken the view that sharing is permissible on the way to unity, whereas traditionally Roman Catholics, Anglicans (including the Church of Ireland) and the Orthodox Churches have taken the view that there cannot be Eucharistic sharing until unity is achieved.

But this is to oversimplify, because within the Anglican Communion there has always been an uneasiness about such a rigid position, and within the last few decades Anglicans have come to see such Eucharistic sharing as indeed a sign of the unity yet to be achieved, but also a means towards that very end.

Anglicanism has been heavily influenced by ecumenical thinking which looks at the sacrament as a sign of something that God gives, the instrument by which he gives it, and the pledge of what he still has to give. Looked at in this way, Eucharistic sharing is a sign of what God wants for the church, a means by which it may be achieved, and a pledge that God wills that we all share together in the messianic banquet in heaven.

Members of the Church of Ireland who remember that the church to which they belong once had grave difficulties about giving Holy Communion to those not confirmed by a bishop (i.e. Presbyterians and Methodists) must therefore enter this debate with all humility. Nevertheless, members of the Church of Ireland have had to weigh very carefully what they have learnt ecumenically.

There was no Canon Law in the Church of Ireland dealing with Eucharistic sharing, so there is no law to be changed to keep up with the custom as it has developed. The Church of England Canon (B15A) reflects exactly what the custom is in the Church of Ireland and in most of the Anglican Communion: "There shall be admitted to the Holy Communion . . . baptised persons who are communicant members of other churches which subscribe to the doctrine of the Holy Trinity, and who are in good standing in their own church."

This is not an attempt to ask Roman Catholics to reject their own discipline, for there are many visitors from other Christian churches who likewise may not realise that they are welcome to receive Holy Communion.

People who come to our own homes are offered hospitality, but we do not take offence if they do not accept. There has been a suggestion that the Church of Ireland might be offended if those deeply committed to the doctrinal statements of another church were to accept this invitation. If this were so we would not issue the invitation in the first place!

The position that sharing in Holy Communion is only to be seen as a sign of a unity that has already been achieved can be argued quite logically, but the fact of the matter would seem to be that events and the pace of the ecumenical movement have passed out this logic. Friends who have shared much in life, both in friendship and in faith, have suffered tremendous pain when they cannot participate fully in a friend's wedding or funeral, or perhaps in an ordination.

That they have felt things to be changing in all the churches on such occasions has been a liberating experience, which surely cannot now be taken from them. It can be argued that there must be the pain of disunity, and to allow Eucharistic sharing is merely to remove the symptoms. It would be a poor medical practitioner who did nothing for a patient to alleviate symptoms.

One sad element that has crept into this debate is negative statements as to the faith of the Church of Ireland. That faith is indeed the apostolic faith as set forth in Holy Scripture and witnessed to in the catholic creeds. The creeds are identical in both Roman and Anglican traditions. There is indeed doctrinal divergence between our two churches, but there is no deficit in the apostolic faith.

In the area of Eucharistic doctrine the best theologians of both Anglican and Roman traditions appointed some 30 years ago by Pope Paul VI and Archbishop Ramsey (then Archbishop of Canterbury) reached the conclusion that there was substantive agreement in the teaching of the two churches concerning the Eucharist.

There are three serious considerations to be addressed in the current debate about Eucharistic sharing. The first concerns the doctrine of the Eucharist itself. We have all allowed our whole understanding of the Eucharist to be influenced too exclusively by the concept of looking back and not sufficiently by that of looking forward. The Eucharist brings us back to the Upper Room and to the Cross, but it also leads us forward to the Kingdom of God, often pictured as a great banquet.

As a result, does our discipline reflect too much of past division and too little of future hope?

Secondly, have churches become too denominational and sectarian in their approach to Eucharistic sharing? The starting point is surely that it is the table or altar of the Lord, and that this would be the most catholic basis for any rules concerning admission to Holy Communion. Common baptism surely demands no less.

The third reason for a reappraisal of Eucharistic sharing is perhaps the most important of all. It is pastoral. It raises such issues as how the churches can join people sacramentally in marriage and deny them the Bread of God together. How can we say to other Christians, you are welcome to come to our sacred meal, we want you there, but you will simply have to watch us eat as we cannot share with you? In a sadly divided world, what would Jesus Christ say to us now?

The context for these questions is perhaps best expressed in the Common Declaration by Pope John Paul II and the Archbishop of Canterbury last year: "We have given thanks that in many parts of the world Anglicans and Catholics, joined in one baptism, recognise one another as brothers and sisters in Christ and give expression to this through joint prayer, common action and joint witness. This is testimony to the Communion we know we already share by God's mercy and demonstrates our intention that it should come to the fullness willed by Christ".

They added that "in many parts of the world Anglicans and Catholics attempt to witness together in the face of growing secularism, religious apathy and moral confusion . . ." Surely this is the context in which the President of Ireland did what is happening in so many parts of our land today?

The Right Rev John Neill is Church of Ireland Bishop of Cashel and Ossory