Why did Our Lord have to suffer and die to redeem us?
Whilst that is a strong statement of it, I can sympathise with the sentiment behind it. So how are we to understand the need of Christ's suffering? Mark, as one would expect, has posted a very well-read approach to this both in his initial post, and in a further one answering the commenter's points.
Here I offer a few personal reflections, really responding to Mark's challenge: How would you answer this? A chance to practise your apologetics.
Of course, ultimately, it is a mystery, something that we cannot fully comprehend due to the limitations of our intellects as created beings, and what's more, fallen created beings. However, to recognise that fact does not absolve us from looking as deep into the mystery as we are able to. So, as so often, I will leap in, in the hope and expectation that anyone who reads this and spots error or heresy will let me know. And so, I may learn something.
I think that to understand the Redemption, one has to understand the Fall, and to understand the Fall, one has to understand the nature of Men and Angels, and indeed God, and His plan for creation. So a short snappy answer is pretty well impossible. But here goes.
In essence, I think the redemptive act had to be a few things: it had to be love-in-action and it had to be truth-in-action and it had to be justice-in-action
It also had to accomplish a few things: to forgive Adam's Original Sin and all our actual sins, to restore to humanity the capacity to enter heaven, to conquer death, and break the Devil's domination.
One could argue that the Father could have done all of this merely by Divine Fiat. But would that have met the criteria of love, truth, and justice?
I would argue that it would not have done.
What we see in Our Lord's passion, death, and resurrection is:
Love: Christ's willingness to suffer and die for us,
Truth: sin is deadly; but both death and sin have been conquered
Justice: the enormity of man's offence (from Adam via Stalin to me...) is offset by the enormity of Christ's sacrifice.
It also confronted precisely those areas in which we are damaged and prone to sin: pride is confronted by Christ's humility and humiliation; power is confronted by his powerlessness; the flesh is confronted by his choosing to suffer; and so on.
Of course there is much more to be said, but I think this is a start. As ever,I'm interested in comments and corrections.