I don't get this at all. And I am usually not stumped by motivational posters. Is this just random, or am I missing the funny?

Why are his teeth not stone too??

OHHH... you are talking about the "poster". Yeah, no... I don't get it at all. The Thing ROCKS! (Pun intended!)

Some artists draw him with teeth and some don't. But it makes sense that they are not stony. His eyes are not stone, and when wolverine cut him, there was flesh underneath. So the rocks are pretty much just where skin would be - not all body tissues.

As for the poster - a gay test is usually a photo of a guy failing to look at a hot girl in the same photo. The other meme referenced is "when you see it, you'll shit bricks," which implies a hidden secret in the image. So is this some combination of the two? Is there a hidden hot girl in this scene?

So wait... all my fishing pictures are "Gay Tests"? What 4 year old thought of this? Still makes no sense. But thanks for the clarification on his teeth.

Oh, and great to see that you did some research on this topic. So yes, the POV is from a hot girl stuck under a rock and the Thing is about to save her.