Why would it be fair to save both?
**Well, who’s to say why the other thief derided Jesus. Maybe he had a difficult childhood which made him cynical. Maybe he had followed some alleged prophet before who turned out to be a fraud? These are situations that are either beyond his control or his intent was good. Who’s to say the other thief would not have done the same as the Good Thief had he had the same opportunities? They were both born in an identical manner, but one had a cynical life thrust upon him and the other did not.
Why should the other thief be passed over because of his circumstances? Surely a merciful and fair Jesus would overlook such things and admit him to heaven, regardless of his worthiness.**
Jesus actually taught in a parable that God is not fair - it was the Gospel reading a week or two ago. It was the parable of the Master of the vineyard, who recruits workers at different times of the day. At the end of the day, the Master instructs the paymaster to pay each worker, with those who served last being paid first. Those were paid a full day’s wage. The others expected a bonus, and grumbled against the Master when they were paid the same daily wage. They had worked all day, and bore the sun’s heat. If the latecomers get a full wage, they ought to get more. That’s FAIR.
But the Master says that each received the agreed upon amount. Had no latecomers worked, they would have no complaint, and would go away satisfied. They were offended because they saw the unfairness of it all. The master asks them, who are you to complain if I want to be generous with my money?
Had the latecomers been paid a fractional wage, and the full-day workers paid a full wage, nobody would have complained (not even the lesser compensated latecomers). That would be FAIR. The full-day workers would be satisfied that the latecomers did not receive the same wage. They would have taken
satisfaction at the impoverishment of others.
The Master was being just (he paid what he promised). The Master was NOT being fair. He was being merciful to the latecomers, and the full-day laborers resented his mercy, because it was not FAIR. They grumbled, even though they had not been cheated. They
felt cheated because someone else who was less deserving got the same as they.
God is not fair. There is nothing about God that is fair. Fairness is NOT a virtue - it is a gateway to jealously and a false sense of entitlement. It is one of humanity’s base (fallen) instincts. Justice is a virtue. Mercy is a virtue. Fairness is the misapplication and corruption of the virtue of justice which opposes the recognition of the virtue of mercy.
You should read
Atlas Shrugged, by Ayn Rand. She is an atheist, but she understands the flaws of fairness better than anyone.