What is "just" about creating someone knowing in advance that that person will ultimately end up in hell for eternity?
Just because Hell is God's eternal prison house, it doesn't mean that anyone is destined to go there. In the same way, just because there are prisons in our countries, it doesn't mean that anyone is destined to go to prison. Prison is not there just to punish criminals, but also to protect innocent, law-abiding citizens from criminals and their acts.
No one goes to prison for nothing (and don't distract by going on about innocent people going there through a miscarriage of justice, because that is not what this thread is about). A person ends up in prison because they did a criminal act which, by law, sentenced them to a term in prison. This is normal justice. Without that, every innocent citizen would be at the mercy of lawless criminals who would rape, pillage, and murder without restraint. All we have to do is to look at countries and communities where the rule of law has broken down.
It is the same with God. The Old Testament prophets warned Israel and Judah that God's judgment would result if they continued to reject Him and worship idols. False prophets said the opposite - that everything is okay because God is a God of love and He will not punish the nation but will continue to protect it from its enemies in spite of its worship of idols. But history tells us that Israel and Judah went to custard and were taken over by the pagan nations around it.
In the same way, there is the warning that those who reject God and His Son Jesus Christ will be sentenced to God's eternal prison house which we call Hell. This is not just to punish rebellious and criminal sinners who reject Christ, but it is to protect and insulate all those who love God and put their trust in Christ from the corruption and harm that godless sinners will bring on them if they have to share heaven with them. God has one strict rule about people entering His heaven. They have to enter through the narrow gate of faith and trust in Christ as their personal Saviour. To be part of the great feast of heaven they have to be wearing the correct wedding garment - which is the righteousness of Christ. Without it, they will not be permitted to enter heaven. This is no different from many nightclubs who demand a certain strict dress code for entry. The bouncer at the door might love you to bits, but if you are not wearing a tie, he cannot, through the rules of the club, let you in.
So, if rebellious ones who will not embrace Christ cannot enter heaven, where else can they go? The only other place is the "outer darkness where men shall wail and gnash their teeth" that the scripture speaks about. There is no other place than the place well call hell.
In fact, I would seriously doubt the truth of God's love toward me and my daughter, if we had to share heaven with the low-life, Christ rejecting hockey puck who raped and infected her with an STD when she was just seventeen.
