"I have to believe in God," someone once told Rabbi Harold Kushner, "so that I have someone to blame, someone to curse and shout at, when I think of what I've gone through." He is almost unique in this brief but very full book; he has been driven to religious belief by a problem that more often drives people away: the problem of evil. Most of the time, the atheist is not bothered, at least philosophically, by what Krushner calls "the unfair distribution of suffering in the world" -- the sheer randomness of phenomena when examined from a moral or emotional point of view; the fact that the good do not always prosper and the wicked frequently seem to go unpunished.

His subject is one of the basic concerns of those who choose to believe in a benevolent and all- Book World WHEN BAD THINGS HAPPEN TO GOOD PEOPLE. By Harold S. Kushner (Schocken. 149 pp. $10.95) powerful god, and it has filled many a heavier volume than this without reaching any solution satisfactory to all shades of religious belief. Otherwise, when someone came to him for comfort, Kushner could simply refer him to the definitive book, or supply a brief paraphrase uttered in properly consoling tones. Instead, despite centuries -- millennia -- of work on the subject, there is no better answer than the bleak summary of the situation: "Whom the Lord loveth, He chastiseth."

The problem hardly existed for such ancient, polytheistic cultures as those of Greece, Rome and Scandinavia. Their gods tended to be people much like themselves -- larger-than-life humans who got drunk, lied, cheated, stole and indulged in fornication with hardly a thought for the happiness or fair treatment of mere mortals in the world below. Sometimes, these gods capriciously tormented humans, particularly with plagues, thunderbolts and other natural phenomena. The extreme statement of this situation, like so many others, is to be found in "King Lear": "As flies to wanton boys are we to th' gods. They kill us for their sport." A problem, perhaps, but not a philosophical or theological problem.

At another extreme is the solution offered by such thinkers as Mary Baker Eddy: If there is an omnipotent and benevolent god, clearly evil does not exist and those who seem to perceive it are simply in error. In between are those systems that postulate a future life -- either in Heaven and Hell or here on earth in reincarnations governed by a rule of karma. God may seem to be acting unjustly and capriciously at the moment, according to these systems, but all will be straightened out in due time -- or in eternity.

One of the most original contributions to the millennial dialogue on the subject was that of Zoroaster, who developed the concept of dualism: The benevolent deity is not the only supernatural power at work in the world; there is a power of darkness that also wins at least occasional and limited victories, and there is a cosmic struggle under way between these two powers. Finally, one might argue an answer of sorts from the perceptions of Teilhard de Chardin: God, like humanity and all the universe, is in the process of evolution; if the system still has a few bugs, we may hope that they will be worked out in due time.

After so many minds have looked at the question and produced so many at least partial answers, can a rabbi from a Boston suburb hope to make a fresh contribution? Harold Kushner felt that at least he had to try, after the death of his son, Aaron, from a rare disease called progeria, "rapid aging," which gives children the symptoms of old age and kills them in their early teens. As a believer in God but one who was not completely convinced about the afterlife, he had to work out a rational approach to the problem or see his beliefs shattered. This little book has preserved his faith and is likely to do the same for many others with a similar problem -- though, like all solutions to the problem of evil, it will leave some people unsatisfied.

Part of the question is relatively easy for him. In cases involving human folly and wickedness, which can range from an auto accident to Hiroshima or Auschwitz, there is some kind of answer: God, for philosophical reasons of His own, refuses to tamper with human freedom. Kushner examines some of those reasons and argues quite persuasively that if ones wishes to create a truly human species, one must allow it the real option of being both evil and irrational; otherwise, it is not human.

But why should God be concerned with the freedom of an earthquake or a cancer cell? In pursuit of answers, Kushner ranges through treatments of the subject from "The Book of Job" to "The Bridge of San Luis Rey," as well as a wealth of anecdotal material from his own experience, and offers a variety of possible answers, the most striking of which has some flavor of Teilhard, some of Zoroaster, though he derives it from his study of Job. Perhaps, he suggests, God is not all-powerful; perhaps He is still engaged in a partially finished work of creation, struggling against the forces of chaos, winning some battles and losing others. Perhaps He exists as a source of comfort to humans with whom he has some cosmic problems in common.

This explanation will comfort and enlighten some readers, while others, who must believe in an all-powerful god, will dismiss it as a step backward toward paganism, a god something like Thor and Zeus, who also tried to do the best they could but had problems of their own. Still, for the large number of believers who share Kushner's attitudes, it offers some satisfaction for "our strenuous need to believe that the world makes sense."