The Substance of Things Hoped For: SHORT FICTION BY MODERN CATHOLIC AUTHORS; selected with an introduction by John B. Breslin SJ (Doubleday: $17.95; 314 pp.)

John B. Breslin, editor of this anthology of Catholic short stories, in not unaware of irony in the presentation of this book nearly two decades after the great surge toward ecumenism. Here he produces a blatantly parochial book: not Christian stories, but Catholic stories.

There is another irony: At a time when it is becoming more and more difficult to recognize what it means to be a Catholic ( vide Bishop Hunthausen and Father Curran), it seems easier to recognize a story that is Catholic, and not just because they have monsignori walking around in them.

In the Catholic view, material things are both real and important. So it is not surprising to find these stories vivid: Actions take place, usually swiftly, between and around real things. Dialogue is sharp, and there is a keen sense of locale.

Still, the stories abound in mystery, paradox and surprise. Because the Catholic believes that Christ was incarnated God (“True God, True Man,” as they say), he finds a boundless, often troubling mystery at the very heart of the matter.

And, yes, Graham Greene is represented, as are Ignazio Silone, Flannery O’Connor, J. F. Powers, Morley Callaghan, Muriel Spark and Walker Percy. Those grand names call attention to the fact that this is a collection of modern writers--not contemporary writers.

A few younger writers are included, Mary Gordon for one. But the better Catholic stories are by those writers who grew up when it was custom as much as belief that made one Catholic: You ate fish on Friday.