Classic rock is about heavy hooks, power chords, and tight harmonies, but it’s also about letting loose and enjoying the good times — and there’s no better time than Friday evening, when we pick up our paycheck, punch out of work, and enjoy a couple days of much-needed rest and relaxation.

Talk to enough creative types, and you'll meet at least a few who buy into the notion that it's easier to make art when you're miserable -- which is unfortunate, but it's true that it's tough to write meaningfully about being happy; emotions at the sunnier end of the spectrum tend to come in bright bursts that are meant to be enjoyed in the moment, and they don't often benefit from the type of deep thought required to produce profound lyrics.

The best way to deal with this conflict? Do away with profundity altogether, as Van Morrison did with his 1972 single 'Jackie Wilson Said (I'm in Heaven When You Smile).' Clocking in under three minutes -- a good portion of which is given over to lyrics like "Ding-a-ling-a-ling-ding" -- it may not be Morrison's most quotable song, but that's sort of the point: It's all about a mad rush of delirious happiness; an ode to, as he puts it, letting it all hang out.

As music lovers, we all understand how people can associate emotions with a particular piece of music, and that's what Morrison does here, comparing the feeling he gets when his lady smiles to the way he feels when he listens to a favorite song from his youth. Fittingly, given that this track is one of the purest bursts of Celtic soul he's ever assembled, Morrison chose a classic (and utterly seminal) hit from one of the genre's greatest legends: Jackie Wilson's 'Reet Petite (The Finest Girl You Ever Want to Meet).'

Originally released in 1957, 'Reet Petite' represented Wilson's coming out as a solo artist after leaving the Dominoes. Taking its main title from Louis Jordan's song for the soundtrack of the 1947 film 'Reet, Petite and Gone,' it showcased the more ebulliently soulful side of Wilson's musical personality -- and like Morrison's song, it celebrated love's happiness with a string of repetitive, largely wordless lyrics. But its simplicity didn't prevent the song from becoming a big hit; in fact, the royalties generated by 'Reet Petite' helped one of its co-writers, Berry Gordy, fund the launch of his legendary Motown Records label.

By the time 'Jackie Wilson Said' was released in 1972, Wilson's success had ebbed; although he had maintained some measure of success on the R&B charts (and he'd go on to score his final Hot 100 hit, 'I Get the Sweetest Feeling,' later in the year), he hadn't really released a big single since 1967, when he took '(Your Love Keeps Lifting Me) Higher and Higher' all the way to Number Six on the pop charts. And while 'Jackie Wilson Said' didn't exactly lead to a Wilson revival -- the song itself didn't get any higher than Number 61 on the chart -- it's gone on to become one of Morrison's most beloved songs, as well as a longtime concert staple and a favorite for cover bands and soundtrack supervisors.

All of which is to say that while happiness is often its own reward, expressing that happiness -- no matter how inelegantly -- can be just as important. So you know what to do, classic rock lovers: Start getting happy by pressing 'play' on that video below, cranking up the volume, and letting the weekend start now.

Listen to Van Morrison, 'Jackie Wilson Said (I'm in Heaven When You Smile)'

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