Where does the phrase 'to harp on' something come from?

Where does the phrase 'to harp on' something come from?

Short Answer

The phrase "to harp on" something—meaning to talk or write persistently and tediously on a particular topic—originates from the physical act of playing a harp, specifically the repetitive motion of plucking the same string over and over again.

Origin and Etymology

The verb "harp" has been used in English for centuries to describe playing the musical instrument. By the 16th century, the term began to be used metaphorically. Just as a musician might repeatedly strike or pluck a single note on a harp to create a monotonous sound, a person who dwells excessively on a single subject is metaphorically "harping on" that same string.

Early literary uses can be found in various works from the late Middle Ages and Renaissance, where it often carried the connotation of nagging or tedious repetition. Over time, the phrase solidified into the standard idiom we use today, dropping the explicit mention of "strings" in everyday conversation while retaining the musical imagery.