a good warning may go against the grain; faithful admonitions are un pleasant to hear; faithful words grate upon the ear;good advice jars (/is hard)on the ear; honest advice may sound harsh to the ear; sincere reproofs are disagreeable; sincere words are hard to take
❍ 且‘～利于行，毒药苦口利于病’，愿沛公听樊哙言。(《史记·留侯世家》) ‘Home truths grate on the ears yet are good guide to action; strong medicine tastes bitter yet helps to cure disease.’ I hope you will take Fan Kuai's advice.
忠言逆耳
honest advice may be distasteful to the recipient;honest advice is hard to accept;truth is a hard pill to swallow; truth hurts;faithful words offend the ear;good advice jars on the ear
忠言逆耳zhōnɡ yán nì ěr
逆耳：不顺耳。指诚恳劝人的话，往往使人听起来感到不舒服。good advice jars on the ear, a good warning may go against the grain, Faithful words grate on the ear.