It has recently come to my attention that a simple listing of Simpsons episodes openly dealing with spiritual issues can be a bit difficult to find. Since I have watched an episode every night of my life for the past 15 years (thirteen of those as a campus pastor) it took little energy to create such list. So I hope this helps!
Homer Vs. Lisa and the 8th Commandment (Season 2): Homer steals cable (as American as stealing apple pie!), but Lisa fears for his soul. This is a good episode for bringing up character issues, stealing and integrity. How do we respond when corruption is the norm?
Homer the Heretic (Season 4): Homer skips church and proceeds to have the best morning of his life, thus deciding to never go to church again and develop his own faith. This episode brings up the issues of Church and community. Why do we bother to be a part of something so messed up and annoying (sometimes)?