Blessed is the man to whom the Lord will not impute sin. – Romans 4:8

When you know that sin is forgiven, you cannot be sad as before. The thought of perfect pardon, if it does but fill the spirit, will thrust out gloom, and remove apathy. It will make the lame man leap as a hart: he may still be lame, but he will leap as if he were not. And the tongue of the dumb, even though untrained to speech, shall be made to sing concerning free grace and dying love. When the thoughts are concentrated upon the enjoyment of complete forgiveness, full reception into the divine favor, and the blotting out of sin, then is the heart lifted into the suburbs of heaven. My dear hearers, do you know what I am talking about? Some of you do, blessed be the name of the Lord; but I am afraid that some of you do not; and you never can know the sweetness of mercy until you first have tasted the bitterness of sin. You will never know how grace can heal until you have felt how sin can wound. There is no clothing you till you are stripped; there is no making you alive till you are killed; there is no filling you till you are empty. The Lord filleth the hungry with good things, but the rich He sends empty away. God Himself will never comfort you till you are driven to self-despair; and if you have already come to that, it is a great privilege to me to be allowed to tell you that the fact of forgiveness of sin is not only a doctrine of the creed, but it is a promise of God’s Word. “I believe in the forgiveness of sins:” this is no mere formula, but a realized fact with me. Removal of the penalty, removal of God’s offense against us, the clearing away of all the turbid waters within the heart, and the creation of joy and peace through perfect reconciliation to God-this is a summary account of the forgiveness of sin. It is a blessing vast and rich. ~ C.H. Spurgeon

https://www.blueletterbible.org/comm/spurgeon_charles/sermons/2207.cfm

“Thy sins are forgiven thee.” – Luke 5:20

I do not think that there can be any grief outside of hell that is more terrible to bear than the wounds of conscience. We read that “David’s heart smote him”; and, believe me, the heart can smite as with an iron mace, and smite where the bruise is felt intensely. Give me into the power of a roaring lion, but never let me come under the power of an awakened guilty conscience. Ay, shut me up in a dark dungeon, among all manner of loathsome creatures-snakes and reptiles of all kinds-but, oh, give me not over to my own thoughts when I am consciously guilty before God! This, surely, is the worm that dieth not, and the fire that is not quenched. I do not speak now what I have merely heard of; though, if you will read Mr. Bunyan’s “Grace Abounding,” you will find a striking account of it there; but I speak of what I have felt in my own soul. No pains of body can rival, for a moment, the agonized feeling of the heart, when the hot irons of conviction burn their way through the soul. When God sets up the conscience and makes it a target for His arrows, they drink up the life blood of our spirit, till we cry out and wonder how such anguish can come to a creature so insignificant. Our soul seems too small a cup to contain such an ocean of misery-too narrow a field for so cruel a battle. It is not the Lord that is the author of the misery; but He is giving us up for a while, that we may be filled with our own ways and learn the bitterness of our own sin. When the Lord comes to us with a forgiving word these sorrows are gone like the mists of the morning when the sun arises. We grieve still to think that we have sinned; but that gnawing remorse, that vulture eating up the liver, is smitten with death and the man breathes hopefully again. Though the penitence remains, the torment is removed from me, when God has forgiven me. ~ C.H. Spurgeon

https://www.blueletterbible.org/comm/spurgeon_charles/sermons/2207.cfm

In whom we have redemption through His blood, the forgiveness of sins… – Ephesians 1:7

I believe that the great joy of forgiveness, to the believer, is that God has taken away His anger from him. That sweet hymn, which we often sing, is a paraphrase of a passage in Isaiah-

“I will praise Thee every day,
Now Thine anger’s turned away;
Comfortable thoughts arise
From the bleeding Sacrifice.”

A person has grieved and wronged me. I feel hurt in my mind about it. When I forgive him, I no longer feel grieved or angry with him: I think of him as aforetime, and we are on good terms. If my forgiveness is genuine-and in God’s case it is emphatically so-then there is no resentment left. The offense is as though it had never been committed. I say to the person who did me wrong, “I take a sponge, and I wipe it all off the slate: give me your hand, let us stand as we stood before.” The pardon of sin by God is after such a fashion. He blots out the sin as the Oriental erases with his pencil the record made upon his waxen tablet, so that no trace of it remains. He smiles where else He must have frowned; He gives complacent love where else there must have been indignation and wrath. Do you not think that this is the sweetest way of looking at the forgiveness of sin? In the case of the poor penitent prodigal, it was the kiss of his father’s lip; it was his restoration to his father’s heart; it was the cheering words of his father’s love that constituted to him the sweetest fragrance of the rose of forgiveness. Yes, the Lord Jesus Christ has come, that we poor guilty ones may be restored to the favor of God, and walk consciously in the light of His countenance, because sin is removed. ~ C.H. Spurgeon

https://www.blueletterbible.org/comm/spurgeon_charles/sermons/2207.cfm