There is as much difference between sin in the wicked and sin in the godly—as between poison being in a serpent and poison being in a man. Poison in a serpent is in its natural place and is delightful—but poison in a man’s body is harmful and he uses antidotes to expel it. So sin in a wicked man is delightful, being in its natural place—but sin in a child of God is burdensome and he uses all means to expel it.
– Thomas Watson –
from The Doctrine of Repentance