Where's the justice?

[Drich]

Two non-Christians are going about their life. They have a dispute that ends in one being killed by the other. The one left alive in his/her later years becomes a Christian.

Now, according to theology, that person is going to heaven. The one who was killed is eternally getting punished. Where's the justice? How does the killer go unpunished like that?

Death/murder is the ultimate/unforgivable sin. Denying the Holy Spirit is. the one who died early committed this sin while the one who killed his brother did not.

Justice is served.