KJV:
And ye have forgotten the exhortation which speaketh unto you as unto children, My son, despise not thou the chastening of the Lord, nor faint when thou art rebuked of him:
NASB:
and you have forgotten the exhortation which is addressed to you as sons, "MY SON, DO NOT REGARD LIGHTLY THE DISCIPLINE OF THE LORD, NOR FAINT WHEN YOU ARE REPROVED BY HIM;