John Calvin Commentary Psalms 9:15

"The nations are sunk down in the pit that they made: In the net which they hid is their own foot taken." — Psalms 9:15 (ASV)

The heathen are sunk. David, now raised to holy confidence, triumphs over his enemies. In the first place, he says metaphorically that they were taken in their own craftiness and snares. He next expresses the same thing plainly: that they were snared in their own wickedness.

And he affirms that this happened not by chance, but was the work of God, and a striking proof of His judgment. When he compares his enemies to hunters or trappers, it is not without just ground for doing so. The wicked, it is true, often commit violence and outrage. Yet, in deceits and cunning schemes, they always imitate their father Satan, who is the father of lies. Therefore, whatever ingenuity they possess, they employ it in practicing wickedness and devising mischief.

As often, therefore, as wicked men cunningly plot our destruction, let us remember that it is no new thing for them to lay nets and snares for the children of God. At the same time, let us comfort ourselves with the reflection that, whatever they may attempt against us, the outcome is not in their control. Let us also remember that God will be against them, not only to frustrate their designs but also to surprise them in the wicked schemes they devise, and to make all their resources for evil fall upon their own heads.