Psalms 3:4

Out of his holy hill] i.e. Zion, the seat of Jehovah's worship, where in a special sense He was present. The Psalmist was probably at a distance from Jerusalem. Selah] This word is found 71 times in the Psalter. It occurs in 40 Pss., as well as three times in Habakkuk 3, which is also a Ps. Its meaning and use are both uncertain. Possibly it is derived from a root, meaning to 'lift up.' LXX translates it 'interlude,' while the Jewish tradition renders it 'for ever.' (1) Some think that it is an instruction to the musicians to 'strike up' with an interlude during an interval of the singing. (2) Prof. Briggs suggests that the LXX and Jewish renderings are really two aspects of the same thing: the former ('interlude') denoting the point where the benediction might be sung and the Ps. concluded for that service; while the latter ('for ever') gives the last word of the benediction, which would indicate the same thing. (3) Taking another derivation (from sallem, 'supplement'), others conjecture that the note may indicate the point at which the MS has to be, or has been, supplemented from another MS. It is best, perhaps, just to regard it generally as a 'musical interlude.'