Though the power of sin be weakened by inherent grace in them that have it, that sin shall not have dominion over them as it hath over others, yet the guilt of sin that doth yet abide and remain is aggravated and heightened by it: Rom. 6:1,2, “What shall we say then? shall we continue in sin, that grace may abound? God forbid. How shall we, that are dead to sin, live any longer therein?”—” How shall we, that are dead?” The emphasis is on the word “we.” How shall we do it, who, as he afterward describes it, have received grace from Christ to the contrary? We, doubtless, are more evil than any, if we do it. I shall not insist on the special aggravations of the sins of such persons,—how they sin against more love, mercy, grace, assistance, relief, means, and deliverances than others. But let this consideration abide in thy mind,—there is inconceivably more evil and guilt in the evil of thy heart that doth remain, than there would be in so much sin if thou hadst no grace at all.
– John Owen –
from The Mortification of Sin in Believers, volume 6 of Works, page 51