John Calvin Commentary Psalms 107:10

"Such as sat in darkness and in the shadow of death, Being bound in affliction and iron," — Psalms 107:10 (ASV)

They who dwell in darkness—the Spirit of God mentions here another kind of danger in which God clearly shows His power and grace in protecting and delivering people. The world, as I said, calls these changes the sport of fortune, and scarcely one in a hundred can be found who attributes them to the superintending providence of God.

It is a very different kind of practical wisdom that God expects from us; namely, that we should meditate on His judgments in the time of adversity and on His goodness in delivering us from it. For surely it is not by mere chance that a person falls into the hands of enemies or robbers; neither is it by chance that he is rescued from them.

But this is what we must constantly keep in mind: that all afflictions are God’s rod, and therefore there is no remedy for them except in His grace. If a person falls into the hands of robbers or pirates and is not instantly murdered but, giving up all hope of life, expects death every moment, surely the deliverance of such a person is a striking proof of the grace of God, which shines all the more splendidly in proportion to the small number of those who escape. So, even if many perish, this circumstance should in no way diminish the praises of God.

For this reason, the prophet charges all those with ingratitude who, after they have been wonderfully preserved, very soon lose sight of the deliverance thus granted to them. To strengthen the charge, he presents, as a testimony against them, their sighs and cries. For when they are in distress, they sincerely confess that God is their deliverer; how is it, then, that this confession disappears when they are enjoying peace and quietness?