@sir82: I think they'd expect a little more detail on that. I phrased it like this:
I participated in conventions of the church that my family belongs to where I gave interviews about self development, time management etc.
It doesn't have to sound too formal either. What do you think?
Simon, the problem is they won't ask me for details. They either accept or decline my application, and because of the great amount of equally qualified applicants, they take personal statements seriously, that's why I'm not sure.
Although the fact that I mention words like "self development", "time management" (i truly talked about these things) should clarify that the emphasis is not on the faith.