During Jacob’s grappling with an angel, the angel touched the socket of Jacob’s thigh joint, causing it to get out of place. The account written later by Moses says: “That is why the sons of Israel are not accustomed to eat the sinew of the thigh nerve, which is on the socket of the thigh joint, down to this [Moses’] day, because he touched the socket of Jacob’s thigh joint by the sinew of the thigh nerve.” (Ge 32:32) Many Jews still adhere to this custom, removing the sciatic nerve together with arteries and tendons before eating the animal. This precept is considered by some Jewish commentators a reminder of God’s providence to Israel as exemplified in the experience of the patriarch Jacob, father of the 12 tribes.
Figurative Use. In a figurative sense the Israelites were said to have a neck as “an iron sinew,” meaning that they were rigid, stubborn, stiff-necked. (Isa 48:4; compare Ex 32:9.) God’s spiritual revival of his people was pictured by the bringing together of bones and the putting of flesh and sinews upon them.—Eze 37:6-8.