NET

9 Again, however, pay very careful attention, lest you forget the things you have seen and disregard them for the rest of your life; instead teach them to your children and grandchildren.

Darby

9 Only take heed to thyself, and keep thy soul diligently, lest thou forget the things that thine eyes have seen (and lest they depart from thy heart all the days of thy life; but thou shalt make them known to thy sons and to thy sons' sons),

KJV

9 Only take heed to thyself, and keep thy soul diligently, lest thou forget the things which thine eyes have seen, and lest they depart from thy heart all the days of thy life: but teach them thy sons, and thy sons' sons;