They are fallen under my feet Cast down to the ground, so that I may tread upon their necks, after the manner of conquerors, Deuteronomy 33:29; Joshua 10:24. Thou hast girded me, &c. Thus again, as in Psalms 18:32, he gives God the whole praise of his great achievements and victories. It was he that inspired his forces with resolution and vigour, and thereby subdued under him those that rose up against him Namely, his enemies who joined in battle to oppose and oppress him.
Related Commentaries of Psalms 18:38
Psalms 18:38-39
38 I have wounded them that they were not able to rise: they are fallen under my feet.
39 For thou hast girded me with strength unto the battle: thou hast subduedk under me those that rose up against me.