Possible meanings are 1) this is a metaphor in which he and his army moving very quickly is spoken of as if his feet barely touch the ground. Alternate translation: "by a path on which he moves with great speed" or 2) "feet" represents the whole person and the phrase indicates that this is a path that they have not traveled before. Alternate translation: "by a path that he has never traveled before" (See: [[rc://en/ta/man/translate/figs-metaphor]] and [[rc://en/ta/man/translate/figs-synecdoche]])