The base image was a man wiping away his sweat, showing that whatever the picture was a reply to was seen as tense or a close-call. Numerous versions of this sweat-wiping image were made and this gif is just a collection of a large amount of those variants just to show that whatever it is a reply to was A) REALLY tense/close , B) There are numerous parts of the post that are tense/close, C) Commenter just wanted to post this gif instead of one of the variants alone.