New York City is feeling blessed right now: The Knicks won their first NBA championship in 53 years. The weather is gorgeous. Two double rainbows arced above me within six days. To cap off a glorious June weekend, the Philadelphia-based duo @ (Stone Filipczak and Victoria Rose) recently touched down in Williamsburg for a free Monday night rooftop show that set their psych-folk stylings against a sparkling skyline sunset.

It should have been perfect, but it was windy. Filipczak’s guitar pick blew off the roof and Rose’s skirt caught the Seven Year Itch. The breeze was screwing with the sound system, and the temperature dropped abruptly. When Rose announced that @’s final song would be seven minutes long, the crowd—as trendy and tightly packed as tinned fish—seemed to brace themselves. A divine blessing indeed, then, that this song was “Autosmile,” the illuminating, six-and-a-half-minute lead single from @’s forthcoming second album.

“Autosmile” earns the runtime. From a base layer of naked vocals and anticipatory fingerpicking, Filipczak and Rose dribble in ratchety güiro percussion, tambourine, and fuller strumming that builds to a chorus of uncertain acceptance: “I don’t know how I belong to you, but I do somehow.” The first time Filipczak and Rose harmonize the lyric, they sing a “bare” or “open fifth”—an uneasy interval heard often in the Sacred Harp singing tradition, which characteristically stands without the “third” that determines if a chord is major or minor. The ambiguity fits: “Autosmile” is a labyrinthine love song that forgoes the peaks and valleys of major- and minor-key emotion for the introspection of the winding maze. “If I wished we’d never met I wouldn’t know the way I got here,” sings Rose. “And I’m in a lovely place.”

With references to demonology and sirens, guitar licks that sound a little lute-like, and harmonies that feel chorally precise, “Autosmile” could be a campfire song in the same folk-fusion fairytale where songwriters like Dan English have been jousting about. The song’s most medieval touch is its unironic proximity to God—“I am so blessed,” Rose sings, “I have no doubt.” Seven-minute songs can be a test of faith; “Autosmile” is a reminder of the bliss that awaits believers.