Free Will & Predestination

A very good example of the harmony between predestination and free will is as follows.

100 condemned prisoners are held on death row in a prison. For some reason, an amnesty is given to them, and these prisoners are no longer condemned and they are free to leave the prison. So all the cell doors are unlocked and the guards are instructed not to hinder anyone who wants to go out to freedom.

But after a while, the Justice official comes and finds that none of the prisoners have left the prison, because they are unable to believe that they have been pardoned. He invites all of them to leave the prison, but they do not trust him. They think that it is some kind of trick, so they stay where they are.

So, the official decides to take 50 of those prisoners by the arm and gently lead them out of the prison, while assuring them they are really free and if they allow him to lead them physically out of the prison, they will discover that they are really free. These 50 choose to cooperate with him and they walk to freedom, while the other 50 remain where they are, and the amnesty for them is cancelled so that they will face execution after all.
This explains the doctrine of election, where God elects to save a certain number of condemned sinners. We all started as condemned sinners anyway, so those who are chosen by God to be saved have no more merit than those God does not choose. God is quite free to choose whoever He wants to be saved. If He leaves others in the "prison" to be condemned, He is not being unfair to anyone, because they were condemned anyway. He does not take anything away from them. He merely uses His power of choice to save a number of sinners through his pure grace. If they deserved to be saved, it would be salvation by works and not by grace.

Therefore being saved by grace means that we who are saved did not get what we deserved, which was condemnation, but were given a free gift out of God's grace for us.

Predestination is the act of the Justice official gently leading the 50 out of the prison, and leaving the other 50 behind to their just deserts. The Justice official is not to be blamed for acting unfairly, because the 50 left behind chose not to accept the invitation to freedom.

But the prisoners who were set free did not deserve to be set free. They deserved condemnation and death. But it was through the pure grace of the person who decided to give them an amnesty that enabled them to walk to freedom.