I have a small selection of Bortnyansky's Sacred Concertos. I bought Vol 2 of the set by the Russian State Orchestra, covering Nos 10-16. This is part of the entire set on the Chandos label. As well, I have No 27 which is included in a wider range of Bortnyansky's Orthodox chant by the Estonian Philharmonic Chamber Choir conducted by Paul Hillier.
Bortnyansky is a principal exponent of this kind of work. I wasn't tempted to buy the rest of the set, mainly because I was only wishing to get a good idea of what Orthodox Chant was all about. I like this kind of material a lot - very uplifting and inspirational, one can almost detect the wafting incense. It has a timeless air about it such that, unless one knew, it wouldn't be apparent that the composer is from the "late classical" era, born roughly about the same time as Mozart although he managed to live much longer.
As soon as you've heard just a few of these concertos, the style tends to remain in your mind and it's easy to recognise it amongst other kinds of church choral work. For example, it's nothing like Gregorian chant, which of course is in Latin, and which has a totally different "air" about it compared with the equivalent material from the Russian Orthodox Church. I do like works with choral/religious flavours, and have catholic tastes (small "c"), although by choice I prefer Catholic (large "C").
One of the useful side results of checking out works by Bortnyanky was the discovery of the Estonian Philharmonic Chamber Choir, referred to above, which prompted me to delve further into their other recordings. They're a really splendid outfit and have recorded works, with a quasi-religious flavour, by several other composers like Mozart, Tchaikovsky, Mendelssohn, Gorecki, Part. It's on the Harmonia Mundi label.