Another historical figure giving a different sense to Malachi 4:6 than the one propagated among some homeschooling leaders, is the great American Cotton Mather. In the introduction to the third book of his Magnalia Christi Americana (p.234), he summarizes his exegesis of that passage:
“It was mentioned as the business and blessedness of John Baptist, 'To turn the hearts of the fathers to the children.' After a deal of more ado about the sense of the passage thus translated, I contented my self with another translation, 'to turn the hearts of the fathers WITH the children;' because I find the preposition ‘epi [greek], as well as the prefix ‘bet’ [Hebrew], in Mal. iv.6, whence the passage is taken, to be rendered ‘with,’ rather than ‘to.’ The sense therefore I took to be, that John should convert both old and young. But further thought hath offered unto me a further gloss upon it: ‘to turn the hearts of the father to the children,' is to turn the children by putting the hearts of the fathers into them; to give them such hearts as were in Abraham, and others of their famous and faithful fathers.
“Reader, the book now in thy hands is to manage the design of a John Baptist, and convey the hearts of the fathers unto the children.”