Ok, so in the season 5 episode 11, the last words Fyodor says are "Eli, Eli, lama sabachtani? "
(which means "My God, my God, why has Thou forsaken me) and as someone already pointed out it's definitely a reference from the Bible from Psalm 22. But my first thought was actually the poem from Silvije Strahimir Kranjčević. The name of the poem is" Eli, Eli lama azaftani!? " which also means "My God, my God, why has Thou forsaken me". The poem's main themes are sin, death and how Jesus died for nothing because people can't appreciate the sacrifice he made for them. So the author portrays humanitys future very pessimistically because the mankind as a whole can't achieve humanity, an individual yes, but as a whole no. On verse says "We kill, God, because of you-Hosana" (couldn't find the english translation of the poem, so I'm gonna translate some verses from my own language to the best of my abilities). Next, a crude translation of some verses so you get the point of how he describes humanity:
"Besides ancient blood and beneath the dry tree/Millions weep: O justice, o *bread! (*food) / To abolish slavery, circus and *hijenu (*real meaning, according to my language's dictionary is 'someone who makes life worse for an already unlucky man') / So you can bring humanity in christian arena"
"Little girls naked, but beside them sated judges/Ah, they would have *dignity (*pride), were it not for their stomach/And shame and misery and insults and tricks/And sighs and lies and many desperate tears"
The poem ends with Jesus seeing all of this and crying out "Eli, Eli, lama azavtani"
Fyodor's whole thing is that he wants to free the world from sin. And this poem also kinda wants that but doesn't believe it's possible. Both are heavily enspired by the Bible, so it makes sense that some themes are corelated.
In the end, this isn't really a theory, but just a thought I had while watching this episode and decided to write this post. It most likely doesn't means anything.
I also think it's funny that all three Fyodor, Gogol and Kranjčević are Slavic realism writers.