The massed voices of choral music are ideal for contemplating existential matters, if only because of the voice's fundamental humanity. Not every composer reached that elevated zone at the opening of the Crossing choir's Month of Moderns festival Sunday at Presbyterian Church of Chestnut Hill. All the better to appreciate music that did hit the infinite, sometimes with texts familiar from having been recast in pop songs.

The festival is titled "Seneca Sounds," after the ancient Roman philosopher, but isn't as daunting as it might sound. Seneca often reads as if written yesterday, and his ideas are full of elemental clarity on core issues of existence. Two of the program's six pieces were based on Ecclesiastes, and not the whitewash job Pete Seeger did on those biblical texts in "Turn, Turn, Turn." Pelle Gudmundsen-Holmgreen's Igen and David Lang's Again (same title, different languages) contemplated birth, death, destruction, and healing with what Lang calls "a strange equilibrium of hope and futility" - accent on futility.

The 2006 Igen fell into a hypnotically repeating four-chord pattern similar to Gorecki's famous Symphony No. 3, unfolding with an inexorable steadiness that suggests a life trudging before one's eyes. This highly communicative work uses quarter tones with great subtlety and otherworldly effect, suggesting that resolution goes against the nature of the universe - and that can be beautiful. The music unfolded with particularly hypnotic fluidity, partly thanks to director Donald Nally's unerring timing, but also because each of the 24 choristers seemed to have an inner tuning fork.

Lang's shorter, more quietly insinuative Again is based on a repeating six-note descending scale, slowing and breaking apart as treble and bass voices go their own ways, converging on the quietly emphatic setting of the words "I forgot it all before, I will forget it all again," a thought to contemplate. For decades.

Elsewhere in the program, the music's word painting was a litmus test for sincerity. Graphic depictions of a text's pictorial imagery often restate the obvious. And as much as the audience responded to Ingram Marshall's Savage Altars, about Roman soldiers burying the bones of both their own and the enemy's dead, the music seemed concerned with setting the scene, not probing how it felt. The piece also came with prerecorded tape with electronic effects, mostly superfluous.

I much preferred the world premiere of Gabriel Jackson's According to Seneca, commissioned by the Crossing, which set to music Seneca-inspired texts by Gustaf Sobin. The splintered verse prompted disparate, simultaneous musical events, some describing wind, waves, and dust particles but with the kind of imagination that has made Eric Whitacre so popular. Excellent piece.

For pure enjoyment, my vote goes to Mark Winges' The Assembling Landscape, which uses the sound of language but with no real text. Liberated from projecting the meaning of words, the music freely used what seemed like every 21st-century choral effect - dissonances used for shape and tension, dramatic clusters, glissandi - with particular abandon. Not that I'm biased against words.

Contact music critic David Patrick Stearns at dstearns@phillynews.com.