"I don't want to go to Heaven if he/she/they will be there."
Someone recently expressed this sentiment to me, and I'd like to offer a few thoughts.
We tend to think of Heaven far too much in terms of the people who will be there with us. We like to think about Heaven as a place where we will be reunited with our deceased loved ones. That's not the point of Heaven. Our focus will be on Christ. It would be a more biblical emphasis to think in terms of who will be there with Christ rather than who will be there with us. That's not to say we won't be reunited with loved ones as well, just that it isn't really the point. It's God's party, and He can invite whomever he wants. We should just be thankful He invited us.
Many of those who are enemies of God and His people in this life won't be in Heaven. Only those who are converted will. As A. W. Pink pointed out in his book The Attributes of God, this is an act of God's mercy towards His people. We will not be forced to spend an eternity with our earthly persecutors.
Unless they are converted, that is. This might be a bitter pill for some to swallow. "So-and-so lived like the Devil, treated me like Hell, and now I'm stuck with him in Heaven." To those who think this way, I would remind them that they too are rebellious sinners in need of God's grace. They too have wronged others. They too stand in need of mercy and forgiveness.
I would also remind them that those of us who've been converted really are a new creation. We've been born again. The old man is dead. A new man stands in his place. I'm quite thankful that God has recreated me and no longer deals with me on the basis of the person I once was. I shouldn't begrudge another the same blessing.
Moreover, I believe we will actually be overjoyed to meet our former enemies on the other side. Don't believe me? I'll give an example from my own life to illustrate my point:
When I was in middle school, there was an older boy who mistreated me. He was a real jerk. He was also a grade ahead of me, so he soon left for high school, and I didn't see him again for awhile. It was nice. I didn't like him, and I preferred it when he wasn't around. But, eventually, I went to high school too, and we shared a class together. He apologized for how he'd treated me in middle school. We were friendly after that. I know, then, from my own experience, that it is better to be reconciled with a former enemy than to simply be removed from him.
If we eventually meet up with our former enemies in Heaven, we'll be happy to see them. "Even the Jihadis?" you ask. Yes. Even the Jihadis.