Let not thine heart decline to her ways. The verb satah is used in Proverbs 4:15 (where see note) of turning aside from evil; but here, as Delitzsch notes, it is especially appropriate to the case of a faithless wife whose transgression, or declension from virtue, is described by this term (Numbers 5:12).
Go not astray in her paths. The LXX. (in most manuscripts) has only one rendering for the two clauses: "Let not thine heart incline unto her ways."