His feelings on the Imperial Truth remained conflicted. He had not forgiven the Emperor for hiding the true nature of the warp from them all. He did not know if he ever could. That one great lie undermined everything else his father had said. If He had not lied, then history might have been very different.

Theoretical, thought Guilliman, slipping into Macraggian dialectic problem solving. What if He was lying about more than the gods of the warp?

Once, he would never have entertained such thoughts. This living hell had challenged everything he had believed.

‘A modified version of it, yes,’ he said. ‘Reason still has a place amid all this madness.’

‘Some may disagree with that,’ said Mathieu amicably. His eyes glinted shrewdly. ‘As I understand it, my lord, this truth denies not only your divinity, but that of your father.’

‘The Emperor denied His own divinity,’ said Guilliman flatly.

The priest shrugged. Guilliman had seen the look on the priest’s face too many times on other holy men. It was the look of the blindly faithful.

If the Emperor Himself stood up, thought Guilliman, came down off His golden throne and proclaimed ‘I am not a god!’ then they would burn Him as a heretic.

Mathieu exhibited few signs of fanaticism, but the primarch would give it time. The more serene the priest on the outside, the deeper his faith was on the inside, and the deeper the faith, the hotter the righteous fires he might cast you into. There was a balance of humours Guilliman required. His militant-apostolic needed some of that zeal.

But be careful there is not too much fire, Roboute, he chided himself, or you will be burnt yourself.

‘If you do not hold with the teachings of our glorious church,’ said Mathieu ‘then why did you treat with us at all?’

‘Because the Adeptus Ministorum has power, and though it has used that power unwisely on occasion, once the balance sheet is reckoned, I see it is and has been a force for good.’ Guilliman looked the priest squarely in the eyes. The priest tried and failed to return his gaze. ‘I need the Adeptus Ministorum. I need their support. The turning of the galaxy depends on their approval, though I may wish it were not so…’ He paused. ‘I intend to end the Indomitus Crusade and divide the fleet, frater, and I would have the blessing of the Ecclesiarchy – both for my men’s morale, and to present a united front to those who would sow division within the Imperium.’

‘You do not need to ask for the Adeptus Ministorum’s blessing, my lord. Any of my peers, any cardinal or episcope, would have leapt at the chance to proclaim your divine will.’