Without going into spoilers, my Inquisitor has taken his first steps along the path of a follower of Karana – the god of Storms. As a benefit of having shown a certain amount of devotion he now has his own shrine to Karana for his house.
This shrine is not just a decoration for his house or object of devotion though. It actually gives access to a set of faction rewards for his religion based on how much he has done to impress his chosen deity. Rather a neat mechanic if I do say so myself! I suppose a guild hall could have multiple shrines to more than one deity to cover any religious diversity in the guild?
A cynic might say this is just another rep grind, but the key thing to bear in mind is that the religion system is purely optional and, IMHO, a great alternative character development idea.