Local churches remain invaluable to their communities, the Moderator of the Presbyterian Church of Wales will say tonight.
While some may have only a handful of members, the Reverend Dafydd Andrew Jones says the nation's chapels should be nonetheless cared for and valued as the place where people can come into contact with the Gospel.
In his final address as Moderator, Mr Jones will argue that the Church as a whole must concentrate all its resources on facilitating local worship and training local people.
This means treasuring and caring for the 640 chapels belonging to the Presbyterian Church of Wales.
"She is our treasure and most precious resource," he will say. "It's no Merched y Wawr (Welsh voluntary women's group) or WI, no football, rugby or rotary club.
"The local church is the body of Jesus Christ in the local community, his eyes and ears, his hands and feet: it is she which has the task of making his gospel real, alive, touching people where they are – this is why she exists.
"But the decline in worshipers suggests that what we do is not relevant to the way most people live their lives or think about life. Ironically, there is a general interest in spirituality today. But the churches and the faith are obviously not reaching this feeling of 'other'."
Mr Jones will deliver his address tonight in Aberystwyth, where the Church is meeting for its annual General Assembly.
He will go on to say that the Church must adapt its structure to make it easier for local churches to implement their vision.
Churches without a minister must also be better supported, he will say.
Following The Gathering conference held last October to discuss the possibility of uniting five of Wales' Christian denominations, he will emphasise the need for different denominations to come together.
"Working together is not enough as there is often a hidden motive - to remain apart," he will say. "Ecumenism calls for commitment to the work of the Lord Jesus and nothing else, 'so that the world may believe.'
"Let us not miss opportunities and add to the fragility, because what has struck me more than anything this year is the brittleness of the Christian witness and the need for a commitment to the Lord and not to our divisions."
He will urge Christians to see the "possibilities and not the obstacles" to unity.
Mr Jones is being succeeded as Moderator by the Reverend Trefor Lewis, of Old Colwyn.