IN a previous life Roy Hattersley, the former deputy leader of the Labour Party, must have been a preacher. Though he was quick to tell the audience yesterday that he is an atheist, Hattersley has not only recently chosen to write about

some of the most significant religious figures in English history - Catherine and William Booth, founders of the Salvation Army; and John Wesley, the man behind Methodism - but yet again demonstrated his exceptional ability to hold an audience rapt. In an unscripted and lively speech about the prickly subject of his forthcoming biography, a life of John Wesley entitled The Brand from the Burning, he combined intellectual rigour with stand-up charisma. The presence of his dog, Buster, in the fourth row was the only prop he needed.

In the mid-twentieth century, many saw allegiance to the Labour Party as a decent alternative to religious belief. Some combined both beliefs, so much so that Harold Wilson once described the party as more Methodist than Marxist. It was not long, however, before both epithets were defunct.

Hattersley's first encounter with Methodism was as a boy, while delivering Labour Party leaflets with his mother. Seeing the risque image of the forces pin-up Jane on the leaflet, a Sheffield alderman spluttered: ''We can't have an

11-year-old boy pushing these through the letterbox.'' He sent him home, where his father enlightened him. ''He's a Methodist,'' he said.

Hattersley confessed early on that ''John Wesley would not be my ideal companion for a walking holiday in the Lake District . . . his transcendental seriousness was difficult for someone of my temperament''. Even so, his heartfelt admiration for the man whom he dubbed ''the leader of the second Reformation'' could not have been more evident. The quality which he most admires

in people, he said is ''believing in something so much and campaigning for it''. In this, as elsewhere in Wesley's

story, his own political convictions shone through.

Wesley is a gift for a biographer: a neglected figure whose influence on British history was immeasurable. More piquantly, his personal life was tortured, his relations with women odd to the point of peculiarity. His road to immortality, however, was his religious vision. Seeing the Church of England neglecting its duty to the new industrial poor, Wesley took to the road, travelling 420,000 miles and delivering 52,000 sermons in his crusade to reach everyone with the message that salvation was attainable for all. ''Without John Wesley,'' said Hattersley, ''there would have been no Billy Graham. But it's important not to hold that against him.''

Sir Frank Kermode, one of the finest literary critics of our day, is deemed to have sealed his reputation with his work on Shakespeare. Delivering the Index on Censorship Lecture yesterday, he spoke about the censorship inflicted on Othello almost from the day the ink was dry. ''The history of Shakespeare's play,'' he said at the start of this fascinating, provocative talk, ''is in part the history of censorship.''

Blighted first by an act of parliament in 1606 which fined any production (pounds) 10 per blasphemy (there were 52 in Othello), the play was doomed from the outset to fall victim to moral squeamishness. Described by one critic as ''one of the most savagely and explicitly sexual good plays ever written'', it has the unsettling quality, Kermode suggested, of ''being disturbingly about everybody''.

There's nowhere better to see the work of the censor than in Verdi's opera Otello, which was the focus of Kermode's lecture. The libretto, written by Arrigo Boito, is immediately set apart from the original by the fact that ''it took Verdi five minutes to get Otello from Cyprus to Venice; it took Shakespeare 45 minutes''. Gone is Desdemona's father's horror at the thought of her daughter ''in the gross clasps of a lascivious Moor''; gone, too, is the couple's harassment on their wedding night by disapproving neighbours.

Picking through the opera with the eye of a literary detective, Kermode highlighted the most significant excisions and refits Boito made on the story. Some, he said, might have been ''unconscious censorship'', as when he vastly reduced the role of Desdemona's maid, Amelia, cutting out her 18-line discussion of the rights of women. This troubling speech (''have we not affections, desire for sport'') was crucial, he said, when seen as part of the growing air of unease and suspense in its blatant hint at ''the limits of female fidelity''.

There was barely a line changed by Boito that did not diminish the original, and Kermode made the audience flinch at the scale of loss inflicted. His conclusion, therefore, was particularly unexpected, and not at all, one suspects, what the index on censorship would have wished to hear. The doctored version by Boito, he said, could depend on

the power of Verdi to supply effects that were not possible

with the libretto.

''The opera,'' he said, ''is almost as potent a study of pathological jealousy as the play . . . these

are two works of genius on the same theme.''

It may have been an outstanding tribute to Verdi, but it left the definition of censorship hanging uncomfortably in the air.

Should any writer whose work is censored simply drop the awkward passages and ask a composer to settle the score? One is left to infer that artistic effect is as important as textual faithfulness. Since the pivotal force in Othello is the pathological fear of infidelity, Kermode could not have reached a more unsettling conclusion.

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