John Wesley on Isaiah 48:17

Teacheth - Who from time to time have made known to thee, all necessary doctrines; which, if observed by thee, would have been infinitely profitable to thee, both for this life and that to come. So that it is not my fault, but thine own, if thou dost not profit. Leadeth - Who acquainteth thee with thy duty in all the concerns of thy life; so that thou canst not pretend ignorance.