He repeats what he had said Psalms 18:32, lest he should seem to arrogate to himself his great achievements and victories mentioned Psalms 18:37,38, and that he might give God the whole praise and glory of them.
Related Commentaries of Psalms 18:39
Psalms 18:39
39 For thou hast girded me with strength unto the battle: thou hast subduedk under me those that rose up against me.