That God is Not Defiled by Our Sins.

And yet, though all things that He established are in Him, those who sin do not defile Him, of whose wisdom it is said: "She touches all things by reason of her purity, and nothing defiled assails her." For it behooves us to believe that as God is incorruptible and unchangeable, so also is He consequently undefilable.

Manich 7.31.1