The function of sin is so that God can express an aspect of his character that can only be expressed through forgiving.
It’s not even that there is anything to forgive because it is God Himself that in the biblical narrative establishes man and supports man, even incites man to become His own adversary (David incited by God to number israel, the law’s function being to make sin increase etc).
For a long time I wondered about this. I could see that the biblical narrative had God doing this but I couldn’t see what for.
It’s so that love could express itself as power and as true power.
Most people think that power is what is portrayed as power. That is as front.
They think that power is attempting to make the world conform to their will, being able to remove discomfort etc… All that they think of as power is really the absence of power in that they wouldn’t do what they did if they didn’t already have a lack, a vulnerability.
Even the act of giving commands hides the truth that he who issues the command is not the sole wielder of power. The commandee has to acquiesce.
Then people call power the acts of coercion employed to bend the victim’s will but this act is itself the evidence, the effect, the symptom of the fact that the person they are being used on is actually not under their control, is not under their power.
Seeing this is the key to understanding the Gospels. It is the key to understanding Jesus and by proxy God.