 Stravinsky said about the texts of his Symphony of Psalms that " it is not a symphony in which I have included Psalms to be sung . On the contrary , it is the singing of the Psalms that I am symphonizing " . This decision was as much musical as it was textual . Stravinsky 's counterpoint required several musical voices to function simultaneously , independent melodically and rhythmically , yet interdependent harmonically . They would sound very different when heard separately , yet harmonious when heard together . To facilitate maximum clarity in this interplay of voices , Stravinsky used " a choral and instrumental ensemble in which the two elements should be on an equal footing , neither of them outweighing the other " . 
