The letter represents samekh support as well as the edges of the fish. In this case, the samekh becomes the tree of life tradition, the path traced. But it is a path that we follow without looking at the risk of being locked up, that shows its rounded shape. The letter represents samekh all our attachments, our passions on which we rely, but act as a trap closes.
Hebrew Letter Sameh Mystical Art אות ס קבלה