giant
Explanation
This is a single-panel comic showing a person peering into a fishbowl containing two fish. One fish says "The giant worried thing in the sky is back!" while the other exclaims "Oh boy, food-rain time!"
The joke is a perspective gag about how fish in a bowl perceive their human owner. The fish have no concept of what a human is; they can only describe what they observe in their limited frame of reference. The human face looming over the bowl becomes "the giant worried thing in the sky," which is both a funny description of a concerned pet owner's face and a surprisingly apt one -- people do tend to look anxious when checking on their fish.
The second fish's response, "food-rain time!", shows the classic Pavlovian association: the appearance of the giant face means food is about to be sprinkled from above. From the fish's perspective, food simply rains from the heavens, delivered by an inscrutable cosmic entity.
The humor works on multiple levels. It is a cute anthropomorphization of fish that simultaneously de-anthropomorphizes humans, reducing us to the simple phenomena that fish can perceive. It also gently satirizes how limited perspectives create strange theologies -- the fish have essentially constructed a rudimentary religion around their owner, complete with a sky deity who delivers sustenance. This resonates with broader philosophical questions about whether our own understanding of the universe might be similarly constrained by our limited perceptual apparatus.