The following is a negative response by a visitor to the Christian belief that those who trust in their morality will end up in hell - that good morality is not what makes a Christian.
Visitor:
I don’t accept a belief system [like yours] that preaches equality. So even if I am a better human being I might deserve less in an afterlife?
Response:
No one is good before an infinitely holy God. Anyone trying to approach the Sun would be instantly burned. How much more sinners trying to approach an infinitely holy God, apart from Christ.
If, because of our foolish decision, we end up stranded on an island and need to get back home 1000s of miles away. Consider: some people can't swim at all, others may be able to swim several miles. One is clearly a better swimmer than all the rest, but compared to the 1000s of miles necessary, the distance is negligible. I may swim one mile, the best swimmer 30 miles, but that only scratches the surface of the length needed for anyone to get home.
In that hypothetical example, I would be the worst swimmer in the group. The scum of humanity. But, in His mercy, God scrapped me off the bottom of the barrel. And His mercy keeps me off, none owing to myself. If there is hope for someone like me then there is hope for anyone.
When the prodigal son returned to his father after squandering everything, seeing him far off, the father ran to embrace him, then put the best robe on him and threw a party. But the older brother was angry with the father and refused to go in and celebrate, thinking he was more deserving. Self righteousness, it turns out, is just as much a sin as the other.