THE SEX Pistols are not easy to love. They are fed up, disgusted and nihilistic, they use nasty words and quite literally spit out lyrics like "I'm only loving myself, mt beautiful self. I've no feeling, no feeling, no feeling, for anybody else." Yet like it or not their music is not only the most exciting thing to happen to rock 'n' roll in years, but the most hopeful as well.

Strong words, but the Sex Pistols do nothing if not make strong music. Unfortunately, that music and its appeal have often been lost in laments on the seediness of punk rock culture in general and the pistols in particularly. It is easy to be put off by their alleged vomiting fit on a flight to Amsterdam or by their scatological TV appearance in England, an appearance that caused a London truck driver to kick in his set and comment, "I can swear as well as anyone, but I don't want this sort of muck coming into my home at teatime."

And nothing is simpler than assuming that a group that can generate this kind of fuss, that has the kind of genius for publicity needed to name its lead singer Johnny Rotten and its bassist Sid Vicious, just has to be bad. But even the briefest of exposures to their album, "Never Mind the Bollocks, It's the Sex Pistols," quickly demonstrates their worth.

There is a caveat. To love the Pistols you must remember rock 'n' roll the way it used to be, remember it before professors of English literature got their tiny hands on it and began publishing concordances of Beatles lyrics. You must go back to the 1950s, back, if you'll excuse the expression, to the roots.

Rock was more than music then, it was a "He's a Rebel" feeling of excitement, of energy aching to break out of puny constraints.Adults hated rock when it began, they thought it was trash or worse, but those who loved the music instinctively felt this vitality even if they couldn't explain exactly why.

Growing older meant a softening of tastes, both for rock audience, who began to drift toward easier listening, and for rock artists. Peter Townsend, for instance, once the driving wheel of The Who, has just come out with an album called "Rough Mix," a wonderful, melodic work, but one that is ever so far away from the raunchy rage he used to specialize in.

Two different rock schools have grown up attempting to fill that void, that falling away from the origins. One might be called the Neo-Rockers, people like Graham Parker, Dave Edmunds, Southside Johnny, even Bruce Springsteen (remember him?). These people make marvelous music, but it is marvelous in a derivative sense, the urgency of early rock filtered through a 1970s context - a pleasure, to be sure, but hardly a hope for the future.

Even worse were the heavy metal people, thudding thumpers like the decadent, mass-marketed Kiss and Blue Oyster Cult - ersatz productions, nurtured on the dregs of the old rock and lacking any real vibrance.

What is most exciting an dmost surprising about the Sex Pistols is the ease with which they have been able to cut through the accumulated barnacles of rock's past 20 years, and to get back to the basic frenetic energy that illuminated Little Richard and the early Who and put it to their own uses. Their energy is crude, but it is genuine, not secondhand, and their aim is true.

To call them nasty is to beg the question. Even their name, which oddly enough calls up memories of one of Shakespeare's bawdiest rogues, is intended as an insult, and the words of their songs, dripping with disgust as they are, filtered through the harshest, most unsettling of vocal styles, simply add to the impact.

"Don't ask us to do a thing, because we're not there, Don't pretend, because we don't care!" they scream in "Pretty Vacant," while "Anarchy in the U.K.," their biggest single in England, starts out with the lines, "I am an anti-Christer, I am an anarchist, I don't know what I want but I know how to get it, I want to destroy." Hardly pretty sentiments, or even esthetically appealing, but in a sense the logical if harsher descendant of simpler songs for simpler times like "Downtown" and "Summertime Blues."

While many of the Pistol's anarchistic vocals relate directly to a fierce sense of class conflict that may very well be uniquely British - "There's no future, no future, no future for you," they drone in "God Save the Queen" - their music is instantaneously understandable, a totally distinctive, though simple style that can't be forgotten or confused once you let it roar out your speakers.

Its basic characteristic is drive, a straight-ahead, monomaniacal urgency, a raw power at once exciting and unsettling. The Sex Pistols are true to their primeval origins, and they make everything else in rock today seem tame, a bit prissy and precious, and suffering from a lack of nerve. Nerve is one thing the group has more than enough of.

The Sex Pistols are the essence of what rock used to be before it got respectable. They are not just the latest media hype, they are the first group in years to have tapped into the central volcanic source of rock. Truly, the Sex Pistols are the people our parents warned us against.