I've mentioned elsewhere that I've started on some Tolstoy. He seems to have two different approaches to Christianity as a thing. On the one hand, he is adamant that the Christian conception of life is self evidently correct and understood by all to be the truth, but on the other hand he writes persuasively about it for those people who aren't yet living that way. In other words, Christianity is obviously right to everyone, and (even though you know this) you should be genuinely Christian (because you aren't living that way now).
He argues for Christianity using reason, and not just as an exercise in faith. Christianity is not a lifestyle choice, one alternative among many, but is the best way for humanity to live. And he argues that this is self-evident to everyone. Although most of his argument is centred around the issue of not resisting violence by force, his view is clear that Christianity is right because it is universally beneficial and better than the social view or the state view of life.
This, of course, puts him in contrast to Kierkegaard. Kierkegaard argued for Christianity on the basis of authority and revelation, not rationality or reason. Through the inheritance of scripture, the written words of people who witnessed Jesus in person, a person has testimony and instructions for how to be Christian, but that this testimony and instruction only has value through the leap of faith.
Both of them make a return to the individual (reader) and argue that as a result of this reason or faith, the right way to live is to obey the commands of Christ to love God and to love one's neighbour. For Kierkegaard, when the individual obeys Christ they become a kind of authentic human, freed from the structures of the humanly-established order to live in genuine liberty. For Tolstoy, individual obedience to Christ awakens the person from the hypnosis of the existing human order, and when many people do this then the kingdom of God becomes a physical thing, freeing people from the structures of states and institutions.
In short, for both writers, the kingdom of God is an emancipatory project for all people, contingent upon the individual obedience to the commands of love.
1. Coincidentally, this is my first exposure to audiobooks as well, courtesy of Librivox. It's an experience entirely different to reading, but I might write about that some other time.