When trying to understand Christianity, two of the most important things are
- To distinguish between what is central and what is peripheral and
- To distinguish between practical and theoretical.
Consider 1. when applied to scripture. There are many passages in the Old Testament which portray God as a kind of tyrant. Yet, in the New Testament in the person of Jesus, God is portrayed very differently. Christians who try to hold onto both kinds of characterizations intellectually, tend to lose both, because they are incompatible.
If you get clear about what is central, then objections to Christianity based on God supposedly ordering slaughter, for example, lose their import. This is because it is very easy to hold that those characterizations are in some way wrong, even if you don’t know exactly in what way. You have to give up something (scriptural infallibility, say), but you don’t have to give up everything, and the former is a lot better from the perspective of Christianity. You can do this because you have clarity about what is central and what is not, scripturally. Christians risk losing everything if they try to make everything central – they create an intellectually and empirically very fragile worldview. If someone prioritizes aspects of Christianity, however, it is not difficult to create a robust worldview.
Consider 2. There are all sorts of theories about all sorts of things in Christianity (as in life in general). Some of these theories lead to things that cause seeming paradoxes, or perhaps seem to have absurd implications. Many theories that have been prominent in the history of Christianity are also very difficult to test. Practices, however, speak for themselves to a large extent, and tend to be much easier to test qua practices.
For example, it is very difficult to test the Catholic theology regarding the Eucharist and transubstantiation of the bread and wine. However, it is relatively easy to test what kinds of effects regular Communion has on people who do so in a particular attitude. For one to lift weights, it doesn’t really matter if some of the standard consensus about why weight lifting causing increases in muscular strength holds up. It just matters if weight lifting does cause increases in muscular strength. The latter is easy to test, and easy to make use of. It would be ridiculous to not weight lift just because you thought some of the standard theory behind why it works isn’t right.