Are all of them vanity... — Once more Isaiah’s favourite tohu — the symbol of the primeval chaos.
Their delectable things... — The generic term used for works of art (Isaiah 2:16), specially for what men delight to worship. (Comp. Isaiah 64:11; Lamentations 1:10.)
They are their own witnesses... — Better, their witnesses (i.e., the worshippers who sing their praises) see not and know not.