But He was wounded for our transgressions, He was bruised for our iniquities: the chastisement of our peace was upon Him; and with His stripes we are healed. – Isaiah 53:5
Sin…is something abnormal. It was not in human nature at the first. “God made man upright.” Our first parent, as he came fresh from the hand of his Maker, was without taint or speck of sin—he had a healthy body inhabited by a healthy soul. There was about him no tendency to evil. He was created pure and perfect—and sin does not enter into the constitution of man, per se, as God made it. It is a something which has come into us from outside. Satan came with his temptation and sin entered into us, and death by sin. Therefore, let no man, in any sense whatever, attribute sin to God as the Creator.
There would be no need to talk about healing if sin had not been regarded by God as a disease. It is a great deal more than a disease—it is a willful crime—but it is still a disease. It is often very difficult to separate the part in a crime which disease of the mind may have and that portion which is distinctly willful. We need not make this separation ourselves. If we were to do so in order to excuse ourselves, that would only be increasing the evil! And if we do it for any other reason, we are so apt to be partial that I am afraid we should ultimately make some kind of excuse for our sin which would not bear the test of the Day of Judgment. It is only because of God’s Sovereignty, His Infinite Grace and His strong resolve to have mercy upon men that, in this instance, He wills to look upon sin as a disease. He does not conceal from Himself, or from us, that it is a great and grievous fault. He calls it a trespass, a transgression, iniquity and other terms that set forth its true character. Never in Scripture do we find any excuse for sin, or lessening of its heinousness, but in order that He might have mercy upon us and deal graciously with us, the Lord is pleased to regard it as a disease—and then to come and treat us as a physician treats his patients, that He may cure us of the evil. ~ C.H. Spurgeon
https://www.blueletterbible.org/comm/spurgeon_charles/sermons/2499.cfm