“I have blotted out, as a cloud, your iniquities.” The Lord promises, to His people, future deliverance, for our hearts cannot be actually raised towards God if we do not perceive that He is reconciled to us. In order, therefore, that He may keep the people whom He has once bound to Himself, He adds a promise by which He comforts them, that they may be fully convinced that the banishment shall not be perpetual, for God, being a most indulgent Father, moderates His chastisements in such a manner that He always forgives His children.
When He says that He has blotted out their iniquities, this relates, literally, to the captives who were punished for their transgressions. And the consequence was that, when God was appeased, they would be delivered. It is a demonstration from the cause to the effect. The guilt has been remitted, for the Jews, as soon as they have been reconciled to God, are freed from the punishment which was inflicted on account of guilt. Yet, there is an implied exhortation to repentance, that they may not only groan under the heavy load of chastisement but may consider that they are justly punished because they have provoked God’s anger. And, indeed, whenever God deals severely with us, we ought not merely to wish relief from uneasiness and pain, but we ought to begin with pardon, that God may no longer impute sins to us. Yes, this passage overthrows the distinction of the Sophists, who acknowledge that guilt is remitted but deny that punishment is remitted, as we have already explained fully in other passages.
The metaphor of “a cloud” has the same meaning as if the Lord had said that He will no longer pursue them in His displeasure or punish them because, when guilt has been remitted, they are reconciled in the same manner as when the sky has become calm, the clouds which intercepted from the earth the light of the sun are “blotted out” and disappear. We must, therefore, reject the diabolical inventions of men, which overthrow the whole doctrine of forgiveness of sins while they openly contradict the doctrine of the prophets. – John Calvin (1509-1564). Comment on Isaiah 44.22.