Sometimes, a cluster of events come along that really illustrates the strength of Philly’s current arts scene. Last week, I saw Edward Albee’s Who’s Afraid of Virginia Woolf? by Theatre Exile. On Sunday, I’ll hear Don Carlo at Opera Philadelphia. In between, I attended Leonard Bernstein’s Mass, with forces including the Philadelphia Orchestra, and conductor Yannick Nézet-Séguin.

Three shows in a week isn’t that unusual for me. What is different here is the scale of those shows. Virginia Woolf may have only four characters, but it’s an epic – and really, really hard to pull off. Many think Don Carlo is the grandest of all Verdi operas.

And Bernstein’s Mass? It makes the other two look small. According to the Philadelphia Orchestra, there are 250 people taking part, including singers, dancers, a marching band, and (on opening night, at least) some Mummers. Nézet-Séguin himself described it as “the pinnacle” of his requiem series with the orchestra, and “a dream” to conduct.

Mass, which premiered in 1971 as part of the opening festivities of the Kennedy Center, is famously a hybrid even by hybrid standards – part religion, part social politics, part drama, and part musical. The subtitle is “A Theatre Piece for Singers, Players and Dancers,” and even that minimizes its ambitions.

At the same time, I think the first five minutes tell us what we need to know. Mass begins with a recorded voice, heard over loudspeakers – a coloratura soprano, singing ornamented phrases the to the “Kyrie eleison” text. It’s pretty and impressive, yet somehow empty. Moments later, a young man (the Celebrant) arrives, clad in a t-shirt and jeans – and the recorded voice gives way to his live performance of a ballad. “Sing God a simple song,” it begins.

For me, the fundamental points of Bernstein’s piece are these: How are we to worship today?; also, what is the appropriate language to express – and challenge – faith?  If these are the questions, the whole of Mass is the wildly complicated answer.  In terms of words, its language is a combination of Latin, English, and something that’s not quite either (it’s scat, or be-bop).

The musical language is… well, it’s Leonard Bernstein, which means a little bit of everything.  Bernstein fans will certainly recognize his style – I mean, styles (plural) – throughout. In the first 15 minutes, I wrote down the following: On the Waterfront, West Side Story, Trouble in Tahiti, Chichester Psalms, Candide – all these and other Bernstein scores have echoes in Mass. It’s not that he reuses specific material – but the range (jazz, rock, opera, and more) is very characteristic, as is the pulsating, vibrant way he deploys them.

I also found links to work not by Bernstein.   At the time of Mass’s premiere, Hair was four years old, and Godspell would open a few months later (in fact, Stephen Schwartz collaborated on parts of Mass). I thought a lot about those works – how they invoke a sense that youth-on-a-quest are the new apostles, and how both these works and Mass are very much “Happenings,” as we called them at the time.

What Mass is not – deliberately, I think – is cohesive. I’m not sure that’s a problem, but for myself I find it successful only in stretches. I’m not persuaded by Bernstein’s more conventional classical vocal writing – a soprano solo about her husband in prison is some of the weakest music in the piece – nor by the more rock parts of the score (which aren’t really rock enough).

But there’s quite a bit of beautiful and very stirring material in the mix. The Celebrant’s “Simple Song” is probably the best-known excerpt, though I prefer his later solo, a ravishingly spare setting of the Lord’s Prayer, which later becomes a plaintive ballad, “I Will Go On.” The final section, where a boy soprano joins the Celebrant, is a sure-fire crowd pleaser.

If Mass doesn’t come together in a traditional sense, it would be hard not to be swept up by its aggregate power. I can’t imagine a better argument for it than the production (and really, that’s what it is) at the Kimmel Center.

Nézet-Séguin’s affection for the piece was palpable throughout. The Philadelphia Orchestra played with awesome energy, as well as the requisite tenderness. Kevin Vortmann was a superlative Celebrant – the role requires a singer with classical baritone resources, as well as a sense of pop style, and an easy float at the top – Vortmann has all of this, and is also a good actor. The featured boy soprano, Douglas Butler, was excellent. (In the evening’s most touching moment, Yannick coaxed Butler out of the wings for an extra solo bow, where he was visibly overwhelmed by the cheering crowd.) The mixed ensembles – singers, dancers, actors – were all up to their challenges, though the “theatre singers” group had the additional problem of using amplification in the resonant Verizon Hall, which isn’t an ideal mix.

Had I seen Mass at another time, I might have categorized it as an historical curiosity, rooted in a world of protest (but with a nod toward hope) that has passed us by. But through a coincidence of timing no one could have anticipated, the first performance in this series took place at the height of the Freddie Gray protests – in fact, there was a large demonstration in front of Philadelphia’s City Hall, just a few blocks away from the Kimmel Center.

So much for history. Whatever Mass may – and may not – be, its sentiments and goals are very much part of our present. Bernstein’s work is, in part, a requiem – yet, rarely I have attended a concert that felt more connected to the real-time world of the living.