REMEMBER The Killing Fields? Take the most terrifying scene you can bear to recall. Now remove the man struggling across that sea of rotting flesh to rejoin his family and put in his place a little girl, a child who no longer has a family, a child who has somehow perversely survived as her parents, grandparents, aunts, uncles, brothers, sisters have either perished or disappeared. Now she is fleeing across the killing fields to an unknown place, anywhere, seeking to escape a childhood of horror piled upon horror. When you have completed this exercise, you will have heard an echo of the experience out of which these two books have emerged.

Before you conclude that you could not bring yourself to read even one such book, you should know that the echo is not the whole. Yes, the horrors spoken of are unspeakable and the terrors paralyzing, but the children of these books did not only survive, they triumphed. They learned despite every grim lesson to the contrary to hold on to faith and hope and, with the horrors past, to trust again and to feel compassion.

I read The Stones Cry Out first, and I suggest that this is the proper order, for this story is a muted first-person account of the years of the Cambodian holocaust told by a child who lived through it. The story begins on April 15, 1975 with a motorbike ride. The countryside is aflame, but in Phnom Penh 12-year-old Buth Keo loves to cling on behind her 17-year-old aunt and pretend that the tree-lined avenue is a country lane. On this particular afternoon they hear what sounds like a tire bursting, the motorbike skids to a halt, and they watch in fascinated horror as a bicycler whose head has been blown off pedals on until his bike crashes into the closed gate of the high school.

By the next day the black-clothed youth called the Khmer Rouge have entered the city and Buth Keo's comfortable, sheltered life in a large, loving, extended family turns into a five-year nightmare. In a vain effort to survive and stay together, the family discards all evidence of their bourgeois past including their names. For the bulk of the book Buth Keo is called Met (Comrade) Peuw. Through starvation, exhaustion, disease and mysterious disappearances, Peuw's extended family is reduced to herself and three younger cousins. The children learn to lie and steal and work harder than adult peasants ever had to, and, above all, they learn to show no emotion, for to weep at the death of a parent or to flinch at the sight of an execution or to recoil from mutilated and rotting bodies are capital offenses.

"From time to time we crossed a clearing, where we saw more corpses, heads and limbs scattered about. Each time the Yotears Khmer Rouge overseers burst out laughing. 'You see what happens to people who don't listen to us.!'

"After seeing those horrors, I felt stronger. 'They won't get me!' I think that was when I stopped being afraid of ghosts."

If Gail Sheehy's observations on surviving are true, that was also when Peuw set in motion the line of action that would lead to her own eventual survival and her present life as adopted daughter of Polish emigre's living in Paris.

In an afterword to the English translation, Peuw, now Molyda Szymusiak and in her early twenties, tells where her three surviving cousins are, and adds: "This translation will permit new readers to learn of those terrible years in my homeland, as well as the story of our survival, and the power of love in the human heart."

It is a story which had to be told, for as the title hints, if those who were a part of it had not told it, the very stones would have cried it out.

TURNING FROM this tale to Gail Sheehy's book is to begin the same story, except that the child at the center is only 5 years old when it begins. But suddenly on page 21 I felt as though I had stepped out from a long dark tunnel into a bright room where the radio was blaring. At first I was jarred by the intrusion of the angst of a well-to-do American celebrity and then annoyed. What on earth was this woman whining about? Couldn't she see these valiant children struggling on and on, their nostrils never free of the stink of rotting human flesh?

Yet this annoyance is certainly one of the responses Sheehy intends for us to feel. She even refers to the book she was writing on the day Cambodia fell, the best-selling Passages, as a book having to do with "Elective crises, I might call them now. Luxury crises. At the time I thought of them as universal."

By juxtaposing her own somewhat spoiled, selfish story with the terrible account of the child who half-way through the book becomes her adopted daughter Sheehy forces all of us who are comfortable in our own good land to ask, not only what we should be doing for such children, but far more significantly, what these children might be doing for us.

Because Sheehy is telling the story, she is also examining the implications. What makes it possible for one person to survive circumstances that many others cannot endure? Once having learned the skills of survival, how can the survivor learn again how to trust, how to adapt to a new life in which those skills are no longer appropriate? How can humanity be so inhumane?

This last question receives a chilling answer. We want to think that the Nazis and the Palestinian terrorists and the Khmer Rouge are somehow aberrations, not really human, or at any rate, deeply psychotic.

Sheehy observes that in pictures she has seen of the Khmer Rouge: "They look completely comfortable with themselves."

" 'Of course they were.' Mohm shrugged . . . 'I don't think they see themselves as being cruel. They think of themselves as being very tough and absolutely right. They believe just like' -- she wasn't sure if she should say this, but went ahead -- 'just like President Reagan speaks as the father of the country; he thinks he's doing only great things for America. They believed they were making a better society for everyone.'"

The stories of these children make us face the evil within ourselves. They make us realize that it was the American bombing and secret invasion of Cambodia that made the atmosphere ripe for the Khmer Rouge takeover. We also have to face the fact that even now our foreign policy favors the remnant of the Khmer Rouge. They are now "freedom fighters" on the borders, seeking to recapture Cambodia from Vietnam, and the very child refugees who fled their terrors are now being encouraged by our policy to leave the refugee camps of Thailand and return to fight on the side of their former tormentors. We must examine what evils our national self-righteousness has led us to commit in the past and what evils this self-righteousness urges us to continue.

We can learn, moreover, from these children that most of what we regard as crisis experiences are shamefully petty when seen in the light of their struggles. But most of all we can rejoice with them in the miraculous resiliency of the human spirit and learn from them the power of faith, hope and love in the human heart. These are they, as the Book of Revelation says, "who have come out of the great tribulation." They may be children, but we must sit at their feet.