They should sing these songs in church. Marvin Gaye's What's Going On doesn't simply boast the gospel influence that marks so much of America's most transformative works in blues and R&B; the album actually has the consistently challenging depth and heart-opening heft of sacred music.

Timely and tough but sure of its wider values, What's Going On arrived on May 21, 1971, as one of music's most complex joys – and one of its most important records. There are biting condemnations on the issues of conflict ("War is not the answer," Gaye sings, "Only love can conquer hate"), drug use, thoughtlessness, social injustices and pollution, but also hopeful messages outlining how brotherly compassion can bolster those fighting their way out of these earth-bound travails.

Gaye had broken ranks with the Motown label's smoothly processed hitmaking dynamic after scoring big with a radical reworking of "I Heard It Through the Grapevine": Once a lighthearted nod to romantic paranoia, Norman Whitfield and Barrett Strong's song was plunged into the shadowed heart of a bereft emotional wreck. Gaye, now sporting a once-verboten wisp of facial hair, felt that success gave him the right to more deeply explore his own feelings.

"I knew there was more inside me," Gaye told biographer David Ritz, "and that was something no record executive or producer could see. But I saw it. I knew I had to get out there."

His days were complicated, however, by a foundering marriage, the difficult illness and death of his longtime singing partner Tammi Terrell, and an intensely personal reaction to the wrongheaded initiative in Vietnam. The impasse with Motown over his musical future yawned for months on end.

"He was coming out of a depression," Ritz, who cowrote Gaye's late-period hit "Sexual Healing," later told the Detroit News. "Tammi Terrell had died. He hadn't been working for a year. He was really depressed. This is his way of using art to overcome depression."

Listen to Marvin Gaye's 'What's Going On'

Gaye started by using his brother Frankie's unhappy military service as a platform for the album's opening title track, crafting an intimate experiment in multilayered vocalization, subtle Latin grooves and remarkably topical commentary on war, violence back home and unrest associated with the fight for civil rights. He was just getting started.

"I began to reevaluate my whole concept of what I wanted my music to say," Gaye told Rolling Stone. "I was very much affected by letters my brother was sending me from Vietnam, as well as the social situation here at home. I realized that I had to put my own fantasies behind me if I wanted to write songs that would reach the souls of people. I wanted them to take a look at what was happening in the world."

The mile markers of America's then-growing – and sadly still-relevant – discontent continue to rush by as Gaye dives into his masterwork: He notes "picket lines and picket signs," as veterans are derisively greeted upon their return. Elsewhere, those who remained "can't find no job, my friend / Money is tighter than it's ever been." All of them stand on a fragile globe trembling under the weight of abuse. "How much more can she stand?" Gaye inquires at the end of the timely and hypnotic "Mercy, Mercy Me."

"The world's never been as depressing as it is right now," he told the Detroit News. "We're killing the planet, killing our young men in the streets and going to war around the world. Human rights – that's the theme."

At the same time, songs like "Save the Children" work as heartfelt counterbalances to these dark portents: "Save the babies!" Gaye cries, shattering whatever hopelessness might have seeped into the record. God loves us, he later surmises, "whether or not we know it, and he'll forgive all our sins."

Having built a cathedral to salvation inside his own chest, Gaye then reaches out once more on the rhythmically and lyrically complex "Wholy Holy": "Holler love," Gaye urges, "across the nation."

Listen to Marvin Gaye's 'Inner City Blues'

What's Going On concludes with a quiet warning, as "Inner City Blues (Make Me Wanna Holler)" focuses on the powers that be and "the way they do my life." Ultimately, however, Gaye seems to be telling a final cautionary tale, constructing his own Book of Funky Revelation. This is what's at risk in the unexamined life: chaos and destruction where redemption was once promised.

"I didn't sing loud, I didn't sing hard on that record," Gaye once told guitar great George Benson. "I just tried to express myself. I just let it all hang out."

In so doing, Gaye finally forged a path to the individualism – and conviction – that he'd aspired to for so long. "I didn't know how to fight before, but now I think I do," he'd later admit. "I just have to do it my way. I'm not a painter; I'm not a poet. But I can do it with music."

The title track, "Mercy, Mercy Me" and then "Inner City Blues" made runs up both the R&B and pop charts in the early '70s, forever establishing Gaye as an artist in full. As with the rest of What's Going On, they still crackle with hard-eyed truths. But just as importantly, they're surrounded by a rare and persistent idealism.

"I'm not sure, in 1971, people wanted to hear that we were burning up the planet and we were polluting the oceans," Ritz told CNN. "He got the message across by grooving it up so craftily until you want to hear it over and over and over again."

Along the way, What's Going On became something more: Marvin Gaye's lasting document of faith.


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