Verily I have cleansed
zakah (zaw-kaw')
to be translucent; figuratively, to be innocent -- be (make) clean, cleanse, be clear, count pure.
my heart
lebab (lay-bawb')
the heart (as the most interior organ)
in vain
riyq (reek)
emptiness; figuratively, a worthless thing; adverbially, in vain -- empty, to no purpose, (in) vain (thing), vanity.
and washed
rachats (raw-khats')
to lave (the whole or a part of a thing) -- bathe (self), wash (self).
my hands
kaph (kaf)
the hollow hand or palm (so of the paw of an animal, of the sole, and even of the bowl of a dish or sling, the handle of a bolt, the leaves of a palm-tree); figuratively, power
in innocency
niqqayown (nik-kaw-yone')
clearness -- cleanness, innocency.