'Shackles' in the Bible

He had often been restrained with shackles and chains, but had snapped the chains apart and broken the shackles in pieces. No one could tame him.

because Jesus was in the process of ordering the unclean spirit to come out of the man. On many occasions the unclean spirit had seized the man, and though he was kept under guard and bound with chains and shackles, he would break the chains and be driven by the demon into deserted places.