Grace Checks Residual Sin

Behold the greatness of the gift and the grace of God that an evil so great is not damnable to the pious! The evil thoughts of the pious are stronger than those of the impious. Yet they do not pollute, do not condemn, them. But they do pollute and condemn the impious. Why is this? Is not the identical sin to be found on both sides? Truly, the same sin; but the pious have an antidote, the others do not.... The glory belongs to the grace of God.... When grace is absent, their evil nature condemns those whom grace now keeps from condemnation.

Source: Quoted in Ewald M. Plass, What Luther Says, A Practical In-home Theology for the Active Christian. St. Louis: Concordia Publishing House. 1959 Edition, 10th Printing (1994), p. 614.