"The Simpsons" airs its 500th episode this Sunday night. "At Long Last Leave," like many latter-day "Simpsons" outings, features a story we've seen variations on several times before (including in "The Simpsons Movie"), but also features many funny jokes that affirm my belief that I'm happier to live in a world that keeps giving us new "Simpsons" episodes (especially when they are occasionally as great as "Holidays of Future Passed") than I will be in the one where that inevitably stops. The couch gag in particular is marvelous, and actually made me choke up a bit. 

The show has been on so long, has passed so many anniversaries, that I've run out of deep thoughts to say about the series at this latest milestone. So instead, I will borrow a suggestion from Time's Jame Poniewozik, who took the occasion of the 500th episode to both declare his own favorite "Simpsons" episode ever ("Homer's Enemy," which I've never liked) and to invite viewers to do the same.

I like Poniewozik's insistence on being absolute here. You can't name your 2 or 3 favorites, can't rattle off a list. Off the top of your head, if someone asks you what your favorite "Simpsons" episode ever is, what comes to mind? For me, it's "Homer the Heretic," the third episode of the show's magical fourth season, in which Homer decides to skip church for once, has the best Sunday of his life, and decides that, from now on, he's going to worship the Lord in his own way, as he wisely explains to Marge here:

There are many, many, many "Simpsons" episodes I can easily and immediately accept as someone's favorite, but to me, "Homer the Heretic" captures everything that was and is great about the series: social satire, extraordinary quotability ("'This Things I Believe'"), a good family story, and an innate sweetness in spite of Homer's outsized antics.

That's mine. Your turn. Remember: pick only one, and, if you have time, explain why it's your favorite.