In general, a lot of people totally underestimate the impact of Gnosticism on East Slavic cultures and the Christian world as a whole. Speaking Russian and having no clue about Gnosticism is like using Facebook without realizing your mom can see the porn you repost. Recently, I opened Taras Shevchenko at a random page, and there he is, accusing King David of impiety. Heresy? Hell no, it’s completely in line with Orthodox ideas of "piety" — the most mainstream of the mainstream.
And that's all because this "Christian culture" isn't "Judeo-Christian" in the slightest, since it doesn't inherit a damn thing from Judaism. It's basically a doctrine preaching that fucking is shameful, life is an absolute disgrace, and the entire world is a bitch's pen run by the head bitch. Because of that, a proper lad has to go hard on asceticism, have zero kids, and drop dead in the middle of a hunger strike.
That's exactly why Shevchenko accuses King David of impiety simply because he had children. From the standpoint of Judaism, this is absolute lunacy, but from the perspective of the ancient Iranian schizos (who originated the institution of monasticism), it makes perfect sense.