And, behold, the angel of the Lord came upon him, and a light shined in the prison: and he smote Peter on the side, and raised him up, saying, Arise up quickly. And his chains fell off from his hands. Smote Peter on the side - He struck him in such a way as was just sufficient to awake him from his sleep.
His chains fell off from his hands - The chains mentioned above, by which he was bound to the two soldiers.