Psalms 18:32 - Matthew Poole's English Annotations on the Holy Bible

That girdeth me with strength; that gives me strength both of mind and body for battle. It is a metaphor taken either from a military girdle, or from a common girdle, wherewith their loose garments were girt about them, whereby they were rendered fitter for any action. Perfect, i.e. perfectly plain and smooth, and clear from impediments, as pioneers use to prepare the way for the march of an army. He guided me in all my counsels and enterprises, so that I neither miss my way, nor stumble in it, nor come short of my end.