[Brother Lucian]

Why haven't this been explored more? Could make for some rather interesting tales of how the Word Bearers is trying to break the faith of the Black Templars, seeing in them mirrors of what they themselves used to be.

Or might it be too painful for the Word Bearers to see or face Astartes in the very position they briefly had ten thousand years earlier of outright worshipping the Emperor?

Perhaps add an uncorrupted Pre-Heresy Word Bearer into the mix, whom had been lost in stasis since the Great Crusade. Whom perhaps is mistaken for being a Black Templar when initially discovered, due to his dedication.

 

[Brother Lucian]

From the Eternal Crusader novella:

‘Now is not your turn to speak, Champion. We know of your objections. Confessor, holy father, give me your opinion.’ Halquon, a shrewd man with a sharp face, came forwards. He was young, but a twisted spine caused him to go about perpetually hunched and clutching at his staff, as if he were burdened with the weight of his office. ‘The Ecclesiarchy recognises Chaplain Mordred’s wishes. You will find no objection from our diocese. I cannot speak for all, but the episcopal rede of Ultima Segmentum has voted in Grimaldus’s favour.’ ‘What has the rede to do with our affairs?’ asked Bayard. He was particularly short-tempered, and his lack of respect offended some of the others. ‘Among the Adeptus Astartes, you are the sole followers of the great truth of the Imperium, my lord,’ said Halquon to Bayard. ‘That the Emperor is a god. Your spiritual decisions are of great interest to us.’

The Black Templars have an ecclesiarchy representative onboard the Eternal Crusader as part of their inner circle.

 

[Brother Lucian]

Hrm, author inconsistency maybe. But Eternal Crusader is a prequel to Hellsreach by Guy Haley, and the ecclesiarchal representative was voting in favor for raising Grimaldus to the status of Reclusiarch.


Another snippet from it, they quite idolize their astropaths for being touched by the Emperor.

So loud was the hymn of the Templars as they purged themselves of their shame that at first none heard the second opening of the great doors, nor the intrusion of a different tune. Pure and high, it infiltrated and complemented the harsh, basso-profundo hymn of the transhuman warriors. Beginning softly, so softly that even enhanced Adeptus Astartes senses could not hear it, it rose until it was unmissable. Helbrecht sought its source. Finding it, he fell to his knees. Making her way down the long aisle from the great portal of Dorn came Mistress Anyanka Dei Osper, Astropath Prime of the Ghoul Stars Crusade. A hundred thralls attended her: a dozen at the fore of her procession sweeping the spotless floor with sanctified brooms, lest her purity be compromised. Five rows of cybernetic castrati followed them, singing the song of annunciation. Beyond these came books containing the names of every member of the Adeptus Astra Telepathica ever assigned to the Black Templars and the collected interpretations of their messages. The books were chained to rings sunk into the flesh of bearers whose mouths were sealed by staples of gold. More came – men clutching heavy brass poles topped with candles the thickness of a thigh, censer-bearers, water-bearers, factotums and body servants. Then came Dei Osper’s bodyguard: twenty heavily armed Adeptus Astra Telepathica bonded warriors, each carrying double-handed swords and shields whose heraldry was divided between that of the Black Templars and their mistress’s adepta. Finally, the long train of her robes borne by fluttering vat-constructs, came the Most Holy Mistress Osper. The Black Templars changed their song to one of lesser volume, forming a counterpoint to the choir of cyber-thralls and relinquishing dominance to the voices of the astropath’s servants. As one, they turned to face her and touched their heads to the floor. The Chaplains knelt and bowed their heads except Theoderic, who raised his crozius and shouted,‘Welcome, welcome, bid welcome to Blessed Mistress Anyanka Dei Osper, touched by the Emperor! Pay obeisance, give your awe! Here is one who has seen the light of the Lord of Man!’ He too knelt then. So the Black Templars remained, softly chanting, until Osper had traversed the two hundred metres to their place of gathering. Her procession parted and halted. The songs diminished to a murmur. Her bodyguards pivoted to line the aisle, clashing their blades upon their shields, and knelt, allowing Osper to come forward to greet the High Marshal. The hymns quietened to a drone. ‘Blessed Lady, to what do we owe this honour?’ asked Helbrecht. ‘Too infrequently do you bring the light of the Emperor to us. We thank you for the blessing of your presence.’

 

[Brother Lucian]

Hence the comment of one recovered from stasis to contrast them against each other.