Kierkegaard was a Christian Existentialist philosopher, which is a fairly rare bird, since most of the Existentialists were and are Atheists. He was a communicant member of the State Church of Denmark, which at the time was a traditional Lutheran Church. Today, of course, it has apostatised, along with all the other liberal churches in Western Europe, possible exceptions being the Lutheran Church of Latvia and the Lutheran Church of Finland.
In order to obtain my Bachelor's Degree (one of them) in Philosophy, I did have to read some of Kierkegaard's work, but that was 20 long years ago. I couldn't really be of much help to you on him at this point.