[1][2] In simpler terms, praise is given, but only given as high as mediocrity, which may be interpreted as passive-aggressive.
The concept can be found in the work of the Hellenistic sophist and philosopher Favorinus (c. 110 CE) who observed that faint and half-hearted praise was more harmful than loud and persistent abuse.
[3] The explicit phrasing of the modern English idiomatic expression was first published by Alexander Pope in his 1734 poem, "Epistle to Dr Arbuthnot" in Prologue to the Satires.
[4] According to William Shepard Walsh, "There is a faint anticipation in William Wycherley's Double Dealer, "and libels everybody with dull praise," but a closer parallel is in Phineas Fletcher: The inversion "praising with faint damns" is more modern,[7] though it goes as far back as 1888.
[8] The concept was widely used in literature in the eighteenth century, for example in Tobias Smollett's Roderick Random: "I impart some of mine to her – am mortified at her faint praise".