This one informs him that Jesus exists, and that he says he is not older than humanity or omnipotent. According to this book, at least, Jesus definitely died and rescued more than a hundred thousand people from one of the hells. It's pretty clear there are other stories the reader is expected to have heard.
So one of the first things I wondered was how I got here without being a Christian. The answer is, we don't know. The best guess anyone has for who goes here is that it's somehow related to your personality. It might also be related to participation in rituals intended to cleanse or sanctify. There's been a lot of ink spilled on this topic and we're barely less in the dark about it than people on Earth.
Well, I figured I'd make the best of it. I wasn't as wronged by Christianity as some, and I figured, hey, at least Jesus is trying to do something about all the hells, and they're not his fault to begin with, so if I have to spend the rest of eternity singing his praises I can at least be a little genuine about it. You might be thinking the same thing. And if you're happy about that, don't let me stop you. But before you invest in harp lessons, you should know something very important: Christianity isn't true. Oh, sure, Jesus exists. He even really died for us. But lots of people have died for me who don't own my soul. If it wouldn't make any sense to say it about a firefighter, it probably doesn't make any sense to say it about Jesus.
If you look at the claims in the Nicene creed, they're mostly wrong. We don't know if there's one God. We don't have any reason to think Jesus is his son. We know Jesus isn't older than all worlds and that they weren't made through him. Arguably, "ascending" is exactly the wrong metaphor to use to describe how we get here.
(But if you were looking forward to the harps, nine of the gospel ensembles in town include harpists.)
The book goes on to explain that Jesus is a mostly hands-off ruler (most of the day-to-day governance is done by elected leaders who theoretically answer to him) who sometimes teaches part-time at one of the local universities (all his lectures and books are available online but if you enroll in his classes you can drop in during office hours to talk to him). What his mystery father is is unclear but it might be one of the demons from one of the hells. Also, he can pass on nifty magic powers which people sometimes get strongly enough to pass them on themselves. The waiting list for those is very long. Otherwise, he's pretty ignorable and probably not actually capable of reading anyone's mind even if he had unlimited attention which he does not seem to.
They explain that there are Christians here, but the denominations are divided up differently: there are several sects that think this isn't the real heaven and the local Jesus is an impostor; there's a sect descended from the Cathars but which believes in the physical incarnation of Jesus; there's a wildly popular adoptionist sect with what the author says is absolutely kooky theology (the details of which are not included); there are some of the sects from modern Earth; and, of course, there are a lot of Arians. But the author ended up joining a coven, of which there are actually several around (the book includes addresses for the websites for three of them). The city has a large Jewish population, largely Karaite but the author can also provide addresses for Orthodox and Reform synagogues (what they are or aren't reforming, the reader is assumed to know). There are several pages dedicated to interesting things about local Islamic theology, which has diverged considerably from Earth's sects; unfortunately, very little of it makes sense without some passing understanding of what they're building off of. Mohammad lives on this plane, although not in this city. But it gets weirder than that. There are Greek mystery cults and dozens of other pagan faiths - not revived or reconstructed, so, in some sense, more authentic than the Earth versions, but still very different from the historical versions from having spent so long changing and adapting to new circumstances. In some cases their gods turned out to be demons and in some of those cases they've schismed based on whether they believe their real gods are out there somewhere; in other cases they have no more evidence for their gods than they did back on Earth. There's been some very interesting drama from some of the older groups meeting their modern counterparts in the past few decades. When they even have modern counterparts, which some of them don't.
There are websites and physical addresses given for a lot of different faith communities. Many of them consider helping lost strangers part of their mission statement, and many others are at least interested in welcoming their co-religionists.
It's pretty clear that the evidence for any gods existing at all is extremely scant. No one here is a cleric, unless you count whatever is happening with the powers Jesus is distributing, which are definitely not the usual divine magic. The author practices magic, some sort of alien kind involving lots of ritual and results that are difficult to distinguish from random chance. That seems to be par for the course for local religions.
Also, this book isn't about the other afterlives but it's clear there are several where people are eternally tortured.