Chapter 8, New Beginnings.
Faith is roused from her quiet recital of Admonitions Against The Empyrean (Scholastica Psykana Press MCMXCVII Edition)by the techpriest, and she doesn't need to be psychic to know that his presence in the Temple-Shrine is akin to an octopus crawling out of the oceans to chat with a mountain bear about the weather.
In other words, things must be really frelling bad for him to be here.
She listens to his explanation and her face grows grimmer with every word.
"I have heard that powerful aetheric manifestations can interfere with technology... I believe an Empyrean creature is the source of your sensor fluctuations. It is impossible to localize because the entity in question is massive, so it appears to be everywhere at once. Fortunately, it is not hostile - otherwise a few sensor glitches and nightmares among the choir would be the least of our worries - but it seems to be upset about something. I had been hoping to draw on the Emperor's might to protect us from its fitful thrashings, but it seems that will no longer suffice. I believe we must inform the Lady-Captain of this together, and then I shall endeavor to try and communicate with this entity, to see if it can be placated, driven off, or slain."
Faith has the feeling that any confrontation with this creature will be like a lone Guardsman squaring off against a greenskin Waaaagh!, but there seems to be no alternative to it.
"Please walk with me," she says, as she leads Jak to find the captain and repeats everything she just told him to her.