I always wondered why God would want eternal separation from sinners (which is, basically, the idea of a “hell”). The answer might be that the sinful character of sinners and the holy caracter of God are simply of different quality, in the sense that God finds sin to be “utterly disgusting” and “unbearable to have in ones proximity”. Therefore, holiness means in efffect separation from sin (as always referred to as its definition), but in essence moral purity.
Now it’s a thought with grandeur in it that God vows to forgive the sinner who believes in Christ. Having abandoned the idea that the offering of Christ is something like a “mechanical payment”, something worthy to pay moral debts, I think that it’s an expression of God’s willingness to forgive those who dare to see their fault and accept this forgiveness. (See my separate post on that.) Now, forgiving the sinner does not change the sinner immediately. He’s a man or woman of the same quality as before. Now, what a great mercy, and what a strenuous activity from God’s side, to let all these sinners into his proximity. Even more, to love them. And of course, to teach them until they gradually become more and more holy. But this will be a long way (and I suppose we’ll have a distance to go in the life after this, too …).