"You were Demon-Born, an Abomination in the Eyes of God...I gave you Scripture. I gave you Discipline"
(Salvation through Suffering: Atonement for the Sin of Existence)
Following Lancelot's deadly confrontation with the Trinity Guard, the injuries he incurred had a fair chance of being fatal without treatment. He would be looking at the likelihood not only of death, but of damnation after, either because Father Carden was right & he was damned by for the nature of his birth as well as his final defiance of Carden's teaching, or because Father Carden was wrong & he's damned all of the killing he perpetrated at Carden's direction. Either way, the extent to which he'd been religiously conditioned by his upbringing in Father's care wouldn't be something that would have just deprogrammed itself in the aftermath of fleeing the Paladin camp with Squirrel, especially with the likelihood of the damnation he'd slaughtered countless of his own kind to avoid seeming so imminent.
He would been afraid, whether he believed he deserved it or not. At whether he wished to or not, in his fear he very likely would have prayed. Below are a few select passages of Medieval Catholic Prayers in use by the 11th Century, which Lancelot might have been likely to say, paired with translations into English.
(verses in red are those he omitted from his recitation, prevented from saying them either for personal reasons or other factors)
"Do you love me, Father?...Even if I am damned?"
The show makes it devastatingly clear with this heartbreaking question - both in word & tone - how desperate the Weeping Monk is for the love & approval & comfort of a parental figure. It goes on to use the rest of the scene to confirm what the audience has already begun to suspect, that Carden had some time ago slaughtered the Ash Man's Fey Folk before indoctrinating/brainwashing Lancelot into a self-mutilating fear & hatred of his own Fey nature The book makes it even more clear than the show that Lancelot was - as the show strongly implies - a mere child when his own people were slaughtered, taken young enough that Carden was "the only Father he knew"
With no memory of his Fey parents, or of a mother's love & indoctrinated into a religion that condemned him for even existing, growing up he would likely have sought comfort in the idea of the benevolence of the Virgin Mother Mary watching over him.
Once having begun a "confession", the ingrained servitude of his every act in Father Carden's name having been "penance" for the sin of his existence - an act of "contrition" for his "Demon Birth" that had been offered as his only means of "Redemption" - his psychological conditioning to beseech God's mercy would likely have beaten into him for so long he'd been unlikely to refrain from supplicating himself & begging for Salvation.
The Weeping Monk was conditioned to a belief that by the very nature of what he was born as, he was an abomination deserving of damnation. The foundation of Carden's control over him is a torturously ingrained conviction that his fundamental existence is that of the lowest & most vile of creatures, only raised above that dispicable state by Carden's teachings. Prayers Father Carden had him recite would no doubt have been ones that would reinforce that self-loathing.
Once breaking free of the grip of his flashback & the prayers of self-debasement that had been beaten into him, he likely still would have reached out.
Just as Carden was the only Father he had known, so too had the Christian God been the only God he'd ever known. And despite how Carden had twisted it to his own purpose, many of Lancelot's actions had been out of what he had been mistaught was the way to show his love & devotion to that God.
In his final moments before acting, L'Ancelot "The Servant" likely would have prayed one last time to the God that he'd tried - in the only way he'd ever been shown - to serve. Not for forgiveness or absolution for sins that he knew he could not forgive himself for, but for the strength to face his fear & to accept his own Damnation willingly- not for the sake of wickedness, but for the sake of saving Squirrel.
