Answer:
"What goes around comes around," or in a less metaphorical sense, "The consequences of one's actions will have to be dealt with eventually."
Step-by-step explanation:
As seen here, the man is pushing over a set of blocks that loop around and would later squash him. This is supposed to show how disrupting or harming someone or something (depicted by the man pushing over a block) "comes around" and ends up hurting the person who started it.