I'm atheist, and worked on two separate productions of Jesus Christ Superstar, 20 years apart. There weren't many of us still around from the first production, but the guy who played Jesus the second time had played one of the apostles 20 years earlier (and still had an excellent singing voice).
I was on the props crew the first time around, and ended up doing a few extra things, like making sure the blood capsules were properly filled at the right time (they don't work right if they're not at the right consistency), tying up Jesus before he's brought before Pilate, and reminding the absent-minded actor who was supposed to do the whipping in the "39 Lashes" scene that yes, this was the scene where he had to bring the whip onstage with him (nearly had to chase him into the wings one night when he swore it wasn't the right scene and I shoved it into his hands and said, "TAKE IT!"; later on, he came back down and sheepishly said, "You were right."). The Herod scene in our production had Herod dressed in a jogging suit while lounging in a hot tub, while his court simultaneously ate snack foods and exercised. At the end of it, Herod threw sponges from his tub at Jesus; this resulted in some of the sponges landing offstage in the audience, so every night some of the people in the audience would considerately come backstage to return a sponge they'd found, and "oh by the way, since I've brought back the sponge, I'd love to meet the actors who play Jesus/Judas/Mary Magdalene, etc...." and if the actors were available, we'd allow it. The kids absolutely loved going backstage and meeting the actors and dancers.
The second time, I was more of a consultant (health issues prevented a more active part in the backstage crews). I helped the properties crew head with finding and designing period-appropriate props and set dressing items, and explained some of the historical reasons why some items were the way they were. She was curious as to how I knew this stuff, and I just explained that since some of the things about the play had confused me the first time I worked on it, I'd done a lot of reading in the meantime - the New Testament and a lot of history books, and taken a classical history course in college.
I got an odd phone call from a friend who was on the costume crew. She'd been assigned to make the loincloth, and asked me, "How do I make one? What do they look like?" and that confused me a bit - she attended church regularly, so she must have seen plenty of crucifixes. But she said no, she didn't really remember any details, and they didn't give enough perspective to know how to make one for a real live person.
So I explained that historically there were several different styles, but the one she wanted was basically a strip of cloth wrapped around the hips and tucked in. I told her to get the actor in for a fitting and get his input on what was comfortable and would allow him freedom of movement while being secure enough not to fall off in the middle of the scene. I knew this actor liked to be as authentic as possible, so I wasn't sure if he intended to wear modern underwear underneath (details learned from working with him years before on a different production when he decided on authenticity). I assured her that the actor had a professional attitude, was polite, and wouldn't be embarrassed during the fitting.
There were some interesting differences between the two productions. The second one was much smaller, and while it was okay, it didn't pack the punch the first one did. That first production that I worked on in the spring of 1981 was one of the best times I've ever had. Just try to imagine about 100 people, cast and crew, working together for months to put this show on... and nearly all of us were high on nothing but a good time. It was so much fun, and over the years I've run into some of the people I worked with, and they remember it as being one of the most fun times they've had, too.
I don't have to imagine. I did a couple local community productions as a younger guy, back in the 90s.

I was a rather hippie looking guy, & fit the bill pretty well, but also happen to have a solid theater singing voice, & performed a stellar Peter. Our production included the often omitted duet
Could We Start Again Please, with Peter & Mary Magdalene. I imagine it's often omitted because it can land as a bit of a lull in the show, if done poorly, but ours was actually a highlight, because our singing was pretty engaging. It's one of the tunes in the show that doesn't play as a rock number. It's got real musical theater vibes to it, more like Webber's other shows
We were always proud that our production included all the occasionally omitted numbers, like
Then We Are Decided. Our Caiaphas was an outstanding base vocalist, who went on to play the part in many big productions, including Ten Neeley's final American tour. The guy who played Simon, the years I was there, went on to take on the Judas or Jesus roles over the later years' productions. It was a seasonal thing here in town for quite a long time
But I left town for a while, & when I came back, they'd kind of lost their momentum. I don't think one's been done here in a few years now, which is a shame. I'd always regretted not getting a shot at Pilot, now that I'm older & more fitting to the part. I think it went away mostly because all those producers/directors from back in the day, who also played parts in the show, are old or deceased now
Hell, the theater owner use to play Pilot, & he was too old then. He fell asleep somewhere in the bowels of the building one night & missed his cue for the trial. Caiaphas just started performing his lines... So needless to say, Caiaphas ordered the whipping that night

They started casting other Pilot actors after that lol.
I'm honestly rarely pleased with Pilot performances. Despite how good they are, guys constantly give what I believe to be the wrong interpretation of him. The show already has Jesus, arguably the most sympathetic character ever, & then the show's unique spin has sympathy for Judas too, & then even Mary has some sympathetic vibes. So many guys want to play Pilot like he's a sympathetic character too, but there's just no room for that imho
Sure, maybe he doesn't really think Jesus deserves to get killed, but he will execute him. He's not sympathetic. He's the man, & the man does the ugly things, & in this show, he's more concerned with how history will remember him anyhow. The Pilot from
The Passion of The Christ. THAT'S the guy. Let him sing the songs, but that's who he is. He may not be THE heavy for the show, but he ought to a heavy. That's how I'd play him anyway