From Lutherans Online:

You've voted! Your 10 favorite "You Know You're Lutheran
When..." jokes have been determined.

You know you're Lutheran when...
10. The only meal time prayer you know is "Come Lord Jesus".
 9. All of your casserole dishes have your name on the bottom.
 8. They have to rope off the last few pews in church so the front 
    isn't empty.
 7. A midlife crisis means switching from the old hymnbook to the 
    new one.
 6. You can't imagine a celebration without food.
 5. While wathing Star Wars you hear "May the force be with
    you" and you reply "And also with you".
 4. At potlucks all the men have tableware and napkins in
    their shirt pockets so their full plates are easier to
    carry.
 3. You are at a funeral of a family member who is Catholic,
    and you are the only one who says "for Thine is the Kingdom
    and the Power and the Glory, forever and ever. Amen." after
    everyone else is done.
 2. You sing "Stand Up, Stand Up for Jesus" while sitting down.
 1. You arrive in church and start having a panic attack
    because someone else is sitting in your pew.