{Thou believest that God is one} (su pisteueis hoti heis
theos estin). James goes on with his reply and takes up mere
creed apart from works, belief that God exists (there is one
God), a fundamental doctrine, but that is not belief or trust in
God. It may be mere creed. {Thou doest well} (kal(9373) poieis).
That is good as far as it goes, which is not far. {The demons
also believe} (kai ta daimonia pisteuousin). They go that far
(the same verb pisteu(935c)). They never doubt the fact of God's
existence. {And shudder} (kai phrissousin). Present active
indicative of phriss(935c), old onomatopoetic verb to bristle up, to
shudder, only here in N.T. Like Latin _horreo_ (horror, standing
of the hair on end with terror). The demons do more than believe
a fact. They shudder at it.