False witnesses of God (
pseudomarture tou qeou). Late word, but
pseudomarturew, to bear false witness, old and common. The genitive (
tou qeou) can be either subjective (in God's service) or objective (concerning God). Either makes good sense.
Because we witnessed of God (
oti emarturhsamen kata tou qeou). Vulgate has
adversus Deum. This is the more natural way to take
kata and genitive,
against God not as equal to
peri (concerning). He would indeed make God play false in that case,
if so be that the dead are not raised (
eiper ara nekroi ouk egeirontai). Condition of first class, assumed as true. Note both
per intensive particle
indeed and
ara inferential particle
therefore.