All human beings, the philosopher Donald MacKinnon used to tell his Cambridge students, have a desire for a true judgment on the lives they have lived. They want to submit to the verdict of an arbitrator who will have inner knowledge of the cards they were dealt, and the conclusions they drew about the way to play them; who will comprehend at the deepest level their motives and intentions in face of the pressures upon them and who will have mercy when they whisper the truth.

Such a judge is not obtainable on this earth, MacKinnon observed. This would seem to be what Pope Benedict XVI is driving at in his recent encyclical letter on hope, Spe Salvi, when he says that “I am convinced that the question of justice constitutes the essential argument, or in any case the strongest argument, in favour of faith in eternal life”. This last section of the encyclical, in which the Pope also reflects on human suffering, has resonance in Lent.

The encyclical, like its predecessor Deus Caritas Est, on love, is written in a beautifully precise, taut style. Here is a German professor at his best, drawing from his reflection on a wide spectrum of ideas as he contends with the atheist current in the West which, he is convinced, will be ruinous. The hope on which he dwells is specifically Christian hope.

In contemplating the Judge who is Jesus Christ, the encyclical comes close to poetry. Benedict telescopes the extended chronology of Purgatory into that one moment in eternity - “the heart's time”, he calls it, outside all chronological time, which no longer exists. “Before his gaze,” Benedict writes, “all falsehood melts away. . . The holy power of His love sears through us like a flame . . . At the moment of judgment we experience and we absorb the overwhelming power of His love over all the evil in the world and in ourselves. The pain of love becomes our salvation and our joy.” The Judge, it turns out, is also the advocate on behalf of all souls which have retained their aspiration towards love and truth.

Benedict is talking about the Last Judgment here, but intimations of the encounter of which he speaks can be had even during a person's lifetime, as when fire came down on Blaise Pascal in Paris from about half past ten at night till about half past midnight on November 23, 1654. Overcome by the experience, Pascal encapsulated it on a slip of paper, which he sewed into the lining of his coat, so that it would go with him wherever he went.

Benedict does not believe that any secular substitute for the Last Judgment can succeed. In the West, the Christian conception of a divine judge has faded into the background, he writes, and has been replaced by a conviction that human beings must themselves establish justice. Such a protest against a God who allows so much injustice and suffering is “understandable”, Benedict thinks. But no one will ever find a secular judge who can perform the function that MacKinnon described, nor an answer for centuries of suffering, nor a guarantee against the cynicism of power.

Lenten abstinence is one way of experiencing solidarity with the suffering people of the world. The “centuries of suffering” are considered in the preceding passage of the encyclical. Great strides have been made to control, reduce and conquer physical pain. Yet in the world today there is no less suffering than before, the Pope thinks. Indeed, “the sufferings of the innocent and mental suffering have, if anything, increased”.

There is no “Christian answer” to suffering, but there is a Christian way of using it. Benedict quotes a letter written by a 19th-century Vietnamese martyr in prison under such conditions as to justify describing his situation as being in Hell. Yet the martyr could still praise: “Bless the Lord with me,” he exhorted his readers, “for his mercy is for ever.”

The test of being human, the Pope reflects, is one's attitude towards suffering. A society must be able to accompany and console those who suffer. If it cannot do that, it is not a human society.

One can only guess whether the Pope might have partly in mind here the suffering of his predecessor, John Paul II, who was afflicted with Parkinson's disease d for several years, till in the end he could not speak. Yet he continued “blessing the Lord” till the end. I have a relative, an atheist, who says: “I am not afraid of death any more, because he wasn't.”

Pope Benedict is an Augustinian, and in his writings one can hear St Augustine's radical pessimism about the corruption of the human condition in its natural state. Or perhaps one could better describe it as a “radical realism”, in line with the Lenten injunction to each person in the congregation: “You are dust and to dust you will return.” It is a realism that opens the way to the essence of the Christian faith as a tragic optimism which never loses hold of hope of new beginnings and a final consummation.

John Wilkins was Editor of The Tablet, 1982-2003