While Acts 13: 38, 39 would suggest a close link between forgiveness and justification, they are not the same.
Forgiveness, or pardon, always assumes that wrong has occurred, that an offence has taken place. Thus forgiveness involves the kindness of a person who has been offended passing over faults against himself so that his kindness can flow forth unimpeded by the wrong.
A justified person is one who is made or declared to be right. Justification is a judicial term and always assumes that what a person did was right, but because accusations have been made, or are likely to be made, there is a need to declare that person right. While a justified man cannot be held chargeable with guilt, justification also includes the thought that he is viewed as positively righteous.
In man’s world, a person who needs forgiveness about some matter cannot be justified in regard to that matter. With man such a thing is impossible, but with God all things are possible! With man, a forgiven person can never be justified; with God, a forgiven person is both forgiven and justified. The best of governments might find a reason to pardon or forgive the guiltiest inmate of its jails; but to justify a criminal would be to morally partake of his crime. It would be an immoral action for a judge to declare a man right who was wrong. A judge cannot justify, or declare judicially right, a proved offender; he may pardon, but he cannot justify. God alone can justify a guilty sinner.
Now as my sins are forgiven, remitted, and blotted out (Acts 3: 19), I can understand you saying “Surely, if my sins are blotted out, it is just as if I had never sinned”. Yes, but the blotting out of sins is not justification, but rather forgiveness. For God also can be justified (Luke 7: 29), that is declared right; but you could not say of God that He can be forgiven! Likewise when the Scripture says that God has been justified, it could not mean that He was in a state “just–as–if–He–had–never–sinned”. It would infer that God had sinned.
What sort of persons does God justify? Godly, righteous ones? No, the very reverse! He justifies the ungodly (Rom. 4: 5). Righteousness is reckoned to those who themselves have none, in virtue of their faith (Rom. 4: 5, 23, 24). He does not view me in a state of “just–as–if–I–had–never–sinned” but in a state of positive righteousness. It is a judicial reckoning. It is not that a measure of righteousness has been transferred to me from another, but that in virtue of my faith, God counts me as righteous in exactly the same way that uncircumcision is reckoned for circumcision (Rom. 2: 26). That is, the Gentile is accounted circumcised when he is not. Thus a person is reckoned to be in a state which he is not de facto (actually) in.
Yet who makes such a pronouncement before the whole universe? The Lord? No. The Father, as Father? No, but God, as God, the supreme Judge. So that the reply to the question “Who shall bring an accusation against God’s elect?” (Rom. 8: 33) is “IT IS GOD WHO JUSTIFIES”.
