Acts 16:24-28

who, having received such a charge, cast them into the inner prison, and made their feet fast in the stocks. But about midnight Paul and Silas were praying and singing hymns unto God, and the prisoners were listening to them; and suddenly there was a great earthquake, so that the foundations of the prison-house were shaken: and immediately all the doors were opened; and every one’s bands were loosed. And the jailor, being roused out of sleep and seeing the prison doors open, drew his sword and was about to kill himself, supposing that the prisoners had escaped. But Paul cried with a loud voice, saying, Do thyself no harm: for we are all here.