I first thought of Van Morrison’s “Astral Weeks” as the noise of a drunk determinedly rummaging for something in a room filled with musical instruments. As he digs, acoustic guitars thrum and violins quake; a flute falls and catches the wind just so. He pushes deeper into the room and knocks over a vibraphone—several times—and through it all he mutters to himself about what he has lost.

When I first heard the album, I’d already listened to it several times. I’d reversed Van Morrison’s line of influence, working from Springsteen’s guileless “Greetings from Asbury Park, N.J.”-era emulations back to Morrison’s own “Moondance” and only then, after these and other derivations and precursors, to the confounding “Astral Weeks” itself. The night I first understood “Astral Weeks,” I was cold in the dark back seat of my family’s car, looking out the fogged window as we became helplessly lost en route to a Christmas party.

As the disc finished and looped back to the beginning, I began to find the music inexplicably appropriate to that moment. “If I ventured in the slipstream,” sings Morrison on the titular first track, “between the viaducts of your dream…could you find me…lay me down in silence easy to be born again?” A bass and shaker bob and amble as the guitar noodles endlessly like it’s searching for a part. Midway through the pulsing song, Morrison begins to rattle off impressions like a musical Leopold Bloom. The instrumentation then begins to crystallize around a sighing string pattern. As the strings rise once more, Morrison suddenly belts, “And here I am,” but what he actually says is, “EHiiiYaaaaaallllAaaahm.” For a measure, the song’s impossibly convoluted instrumentation converges around Morrison’s purposeful ineloquence. I realized then that Morrison was searching, too. “I’m nothing but a stranger in this world,” he hazily reflects as the song settles, “I got a home on high…so far away.” He laughs and whispers as the song fades, his lines gamboling about one another.

From then on, I have thought of Morrison’s music as a journey. Greil Marcus articulates this element of searching better than I could hope to in his book “When That Rough God Goes Riding”: “There is in his music from the very first a kind of quest: for the moment when the magic word, riff, note, or chord is found and everything is transformed.” In Irish culture, a voice at that moment is called the yarragh—“the voice that strikes a note so exalted you can’t believe a mere human being is responsible for it, a note so unfinished and unsatisfied you can understand why the eternal seems to be riding on its back,” as Marcus writes. In short, this is the “EHiiiYaaaaaallllAaaahm” that would mean “And here I am” whether or not those were the words Morrison meant to sing. These are the best moments in Morrison’s music—split seconds of sheer joy mingled with unbarred hurt and acceptance when it seems as if he has been using words as placeholders for the deeper meaning that only his fully summoned voice can convey.

That Morrison’s joy cannot be articulated easily is understandable. He had not led a happy life when he recorded “Astral Weeks” in 1968.  After a successful yet somehow unpopular career in Ireland, Morrison came to Cambridge, Mass., to seek his fame. The United States, however, treated him no better.  Legal matters kept him out of the studio, and he took the impasse poorly, angrily enduring a creative dry spell and a bitter attempt at his deportation. Yet this darkness forms the rough-hewn edge to every joyful moment his later work achieves. If there were a universal trope of joyful music, it would be the phenomenon of mounting tension and ecstatic release. Morrison’s voice collapses this arc into a tension that is always present: Though he may triumphantly belt his choruses, it is with the same voice that, kept from song, incessantly called Boston radio DJs with slurred demands for old blues music in the late ’60s.

The lyrics of “Astral Weeks” help explain why he can sound so joyous. The words vaguely call to someone to find him—a “stranger in the world”—so he can be born again. The instrumentation is loose because it too is searching for the build that allows Morrison to unleash his cry of, “Here I am.” These moments of joy, then, are times when Morrison is inescapably himself—a stranger in the world briefly glimpsing his home on high. It is a pure reassurance of music’s potential to be intrinsically joyful, and it is in these depths of understanding and acceptance beyond language that a listener’s soul responds with like joy; that we become strangers in the world, together.

—Columnist Benjamin Naddaff-Hafrey can be reached at bhafrey@college.harvard.edu.