John Chrysostom : The prison shook to disrupt the mindset of the faithless, to set the prison guard free and to proclaim the word of God.… You see how the nature of shackles destroys the shackles, for just as the death of the Lord put death to death, so also the shackles of Paul set the captives free, shook the prison, opened the doors. And yet this is not the nature of shackles, but they do the opposite—they hold the prisoner in security, they do not open up the walls for him. But while the simple nature of shackles is not this, the nature of these shackles is such because of Christ. — CATENA ON THE ACTS OF THE APOSTLES 16.26-28 John Chrysostom : And suddenly there was a great earthquake, so that the foundations of the prison were shaken, and immediately all the doors were opened, and every one's bands were loosed. And why did no other miracle take place? Because this was, of all others, the thing sufficient for his conversion, seeing he was personally in danger: for it is not so much miracles that overpower us, as the things which issue in our own deliverance. That the earthquake should not seem to have come of itself, there was this concurrent circumstance, bearing witness to it: the doors were opened, and all their bonds were loosed. And it appears in the night-time; for the Apostles did not work for display, but for men's salvation. — Homily on Acts 36 Oecumenius : An earthquake struck so great that it awakened the prison guard; indeed the doors were opened, so that he might marvel at what had happened and believe. For these things were not done for display, but for salvation. Were not these seen before by those who were bound? For otherwise certainly all would have fled. — Commentary on Acts