Quote Daniel Davis:
Polyphony (music containing more than one simultaneous note) is a western European invention which arose almost two millennia after King David. It is hardly likely that David had even the concept of a chord let alone a secret one which pleased the Lord.
Not necessarily. Harmony was certainly anathema to the Greeks (who considered the octave to be the only permissable consonant interval). However, there is scant evidence for preceding oral/aural music traditions, but the existence of the lyre with multiple strings suggests that pre-Greek musicians must have been aware of harmony.
Interestingly enough, the word 'anathema' in its original Greek meaning implies 'off-limits', 'a godly offering', although there is no explicit biblical reference for 'special' Godly harmony as suggested by Cohen's lyrics.
In the Old Testament, Samuel I states that "David took an harp, and played with his hand" (16: 23). Might this suggest playing with several fingers like a harpist, rather than strumming guitar-style? Either manner of playing suggests the use of harmony. A harp-like playing style even suggests polyphony in a manner more like Western species counterpoint. But that's another story...