If a person seriously contemplates the hideousness of his sin in light of God’s law, and if he seriously contemplates the reality of forgiveness through Christ’s blood, it is a gospel truth that our minds cannot fully understand. The person who has sinned against God in the worst ways imaginable can have his sins freely washed away by the precious blood of Christ (1 Pet. 1:19, 1 John 1:9, etc). This is a staggering truth that’s hard for us to contemplate! Here’s how John Owen explains this truth of grace:
It is an object for faith alone, which can rest in that which it cannot comprehend. It is never safer than when it is, as it were, overwhelmed with infiniteness. But set mere rational thoughts, or the imaginations of our minds, at work about such things, and they fall inconceivably short of them. Were not forgiveness in God something beyond what men could imagine, no flesh could be saved. This God himself expresses: ‘Let the wicked forsake his way, and the unrighteous man his thoughts, and let him return unto the Lord, and he will have mercy upon him, and to our God, and he will abundantly pardon. For my thoughts are not your thoughts, neither are your ways my ways, says the Lord; for as the heavens are higher than the earth, so are my ways higher than your ways, and my thoughts than your thoughts’ (Is. 55:7-9).
They are, in as is plain in the context, thoughts of forgiveness and ways of pardon of which he speaks. These our apprehensions come short of; we know little or nothing of the infinite largeness of his heart in the matter. They are, as is plain in the context, thoughts of forgiveness and ways of pardon whereof he speaks. These our apprehensions come short of; we know little or nothing of the infinite largeness of his heart in this matter. He that he speaks of is “an impiously wicked man,” and “a man of deceit and perverse wickedness;” he whose design and course is nothing but a lie, sin, and iniquity; such a one as we would have little or no hopes of — that we would scarce think it worth our while to deal withal about — a hopeless conversion; or can scarce find in our hearts to pray for him, but are ready to give him up as one profligate and desperate.
But let him turn to the Lord, and he shall obtain forgiveness. But how can this be? Is it possible there should be mercy for such a one? Yes; for the Lord “will multiply to pardon” (Hebrew). He hath forgiveness with him to outdo all the multiplied sins of any that turn unto him and seek for it. But this is very hard, very difficult for us to apprehend. This is not the way and manner of men. We deal not thus with profligate offenders against us. “True,” saith God; “but ‘your ways are not my ways.’ I do not act in this matter like unto you, nor as you are accustomed to do (John Owen, The Forgiveness of Sin: A Practical Exposition of Psalm 130, p 212-213).”
Indeed – where sin abounds, grace abounds all the more!