Book of a Lifetime: Gilead, By Marilynne Robinson

"The fact is, I don't want to be old. And I certainly don't want to be dead. I don't want to be the tremulous coot you barely remember." As John Ames begins to write a letter to his son, a letter that will be read when he is long buried, he is unaware that this will not be a meditation on beauty, but on the difficulty of forgiveness. Ames, a pastor in the crumbling prairie town of Gilead, Iowa, finds a beauty in creation that almost breaks his heart – a heart now prone to missed beats, flutters, uneven squeezes of the chambers. Water, the house cat, baseball on the radio: these are achingly more beautiful as they will soon be lost. He has come to see his perishability, and the world looks lovely in the light of his leaving it.

The pastor is living out the miracle of his late life. Having lost his first wife and child to a difficult labour 50 years earlier, he has unexpectedly started a new family. After the years spent in the wilderness of his own company, Ames can find only rapture in his wife and his son playing in the sprinkler: "whooping and stomping as sane people ought to do when they encounter a thing so miraculous as water."

The flow of his epistle is, however, suddenly interrupted. A man appears in town, late in the evening, and late in this novel, and Ames's enviable tranquillity is broken. Jack Boughton, small-time liar, petty thief, a man full of slick charm but also rotten guilt, is the thorn in the pastor's side. Ames, who is always attentive to loveliness, cannot see the goodness in God's creature before him. What has Jack done so that he cannot earn the grace of this tender old man? This letter, begun with a rich and full heart, starts to become a warning call to his son: at all costs, avoid Jack Boughton. And for that measure, tell your mother too.

One doesn't need to be interested in faith or religion to be moved by this story of forgiveness. Ames's sourness comes from his envy, from a time when "the beauty of other lives was a misery and an offense to me". Jack had something Ames hungered for, and he threw it away, as if it were a trifle.

As he prepares to meet his maker, Ames must try and forgive him that. It is the last battle of an old man trying to scrub the envy from his heart before it gives up on him. 'Gilead' is about grace, and the struggle to grant it, which, Marilynne Robinson shows, can be as much a secular struggle as a religious one. It is a book of a lifetime for those who believe life does last a lifetime, or for those, like the pastor, who are waiting with sweetness, trepidation, and some degree of regret for the next one.

Naomi Wood's novel 'The Godless Boys' is published by Picador