Jamieson, Fausset and Brown on Psalms 49:4

4. incline--to hear attentively (Psa 17:6; 31:2).

parable--In Hebrew and Greek "parable" and "proverb" are translations of the same word. It denotes a comparison, or form of speech, which under one image includes many, and is expressive of a general truth capable of various illustrations. Hence it may be used for the illustration itself. For the former sense, "proverb" (that is, one word for several) is the usual English term, and for the latter, in which comparison is prominent, "parable" (that is, one thing laid by another). The distinction is not always observed, since here, and in Psa 78:2; "proverb" would better express the style of the composition (compare also Pr 26:7, 9; Ha 2:6; Joh 16:25, 29). Such forms of speech are often very figurative and also obscure (compare Mt 13:12-15). Hence the use of the parallel word--

dark saying--or, "riddle" (compare Eze 17:2).

open--is to explain.

upon the harp--the accompaniment for a lyric.