“The greatest guilt that ever was contracted upon a trembling, shaking conscience, can stand before the efficacy of the blood of Christ no more than the sinner himself can stand before the justice of the Lord, with all their guilt upon him. Flavel, 1.328
Paraphrased by James Dorman IV: Just as: A guilty sinner stands no chance of standing safely before a Holy God.
In similar manner: The believer's sins (no matter how large, or greatly felt) stand no chance of standing safely before the powerful, effective atoning pardoning redeeming forgiving blood of Christ.