John Gill Commentary Psalms 107:16

"For he hath broken the gates of brass, And cut the bars of iron in sunder." — Psalms 107:16 (ASV)

For he has broken the gates of brass The prison doors made of brass, as sometimes of iron, for the security of the prisoners; see (Acts 12:10) . And cut the bars of iron in sunder; with which they were barred and secured.

Hyperbolical phrases these, as Kimchi, expressing how exceeding strong the prison doors were, and the impossibility of an escape out of them, unless the Lord had delivered them; but when he works, no one can hinder; all obstructions are easily removed by him; which is the sense of the words, see (Isaiah 45:2) .

Vitringa, on (Revelation 12:2) , interprets this of the subjection of the Roman emperors to the faith and obedience of Christ.