or SINNIS a son of Polypemon, Pemon or Poseidon by Sylea, the daughter of Corinthus. He was surnamed according to some Pityocamptes, and according to others Procrustes.
Theseus fights Sinis, the Pine-Bender
Sinis was called the Pine-Bender because this was his manner of executing his victims and used to ask travellers to help him bend two pine trees to the ground.
Once the trees were bent he tied his helper's wrists, one to each tree. When the strain became too much, the victim had to let go, which caused the trees to snap upright and rips the victim into pieces.
Theseus kills Sinis and has an affair with his daughter Perigoune, whom Sinis has hidden in a field of asparagus. She bears him a son Melanippus.
He dwelt on the isthmus of Corinth as a robber, destroying the travellers whom he had conquered, by fastening them to the top of a fir-tree, which he curbed, and then let spring up again. He himself was killed in this manner by Theseus.
When Theseus had accomplished this, he caused himself to be purified by Phytalus at the altar of Zeus Meilichios, because Theseus himself was related to Sinis, or according to others, he propitiated the spirit of Sinis by instituting in his honour the Isthmian games.
The name is connected with ripping, expressing the manner in
which he tore his victims to pieces.