This is bugging me, because I'm pretty sure I had it installed on my old computer. It was an FPS, I think originating from Russia. The setting was sci-fi, with a touch of religious mysticism. The protagonist is a soldier for the government, which is a bit of a theocracy, claiming to be in touch with their god, and empowered by them. I think the very first bit of the game involves a small level where you enter a gate, which is either stated, or implied, to be an exit from the afterlife after dying in righteous battle. I remember there were choices as to what skills were taken, ranging from stealth to gun combat to melee combat, before the first level. That first level, I remember there was some sort of a chase after a criminal, with other goons forcing the protagonist into running firefights during the pursuit. After that level, there were a bit on-base, which seemed fairly extensive, involving walking through something like a city, complete with canals. I don't remember if I saw the protagonist, but his fellow soldiers wear golden armor with a lot of tubes and lumps, kind of elephantine in the head shape. After that, the next level had the protagonist fighting in a slum city, I think pursuing some sort of rebel "General". I remember looking up some info on the game, and learning there were multiple paths, including violence, bribing the "General", or convincing him via debate of the rightness of your actions. I'm pretty sure, when I looked up the game, that they said that you eventually come to realize that the government you serve is corrupt. I know, kind of a standard trope.
I think it might have been built on the Deus Ex engine, just based on graphics and the skillset. It might have started life as a mod, but I think they'd licensed it by the time of release.