Proverbs 27:6

Faithful [are] the wounds of a friend
That is, friendly reproofs; which, though they may be severe, at least thought so, and may grieve and wound, and cause pain and uneasiness for the present, yet, proceeding from a spirit of love, faithfulness, and integrity, and designed for the good of the person reproved, ought to be kindly received; see ( Psalms 141:5 ) ;

but the kisses of an enemy [are] deceitful;
flow from a deceitful heart, and not to be confided in, as the kisses of Joab and Judas. It may be rather rendered, "are to be deprecated" ^F25; prayed against, as real evils, hurtful and pernicious; and so the Targum renders it, "are evil". Good is the advice of Isocrates ^F26,

``reckon them faithful, not who praise everything thou sayest or doest, but those that reprove what is amiss.''