This cap is from 5x22 "Swan Song"
Click to see the full-sized cap.
DEAN: "Bvtmon...Tabges...Babalon." (OPEN THE MOUTH OF THE CAVE TO THE WICKED...)
I remember how the pics from the episode came out before it aired and we saw Dean in this great pose with his hand stretched out and it felt like something really momentous was happening. Speculation was that Dean had gotten some kind of power. Turned out it was just reciting Latin and opening the door to Lucifer's cage, but it wasn't any less impressive.
Have a good Friday folks. *hugs*