{With the understanding also} (kai t(9369) no(8b5c)). Instrumental
case of 
ous. Paul is distinctly in favour of the use of the
intellect in prayer. Prayer is an intelligent exercise of the
mind. {And I will sing with the understanding also} (psal(9320)de
kai t(9369) no(8b5c)). There was ecstatic singing like the rhapsody of
some prayers without intelligent words. But Paul prefers singing
that reaches the intellect as well as stirs the emotions. Solos
that people do not understand lose more than half their value in
church worship. Psall(935c) originally meant to play on strings,
then to sing with an accompaniment ( Eph 5:19 ), and here
apparently to sing without regard to an instrument.