Steve Chalke's comments in The Lost Message of Jesus are probably but the visible tip of a mammoth iceberg that is subtlely undermining Scripture's rich but clear revelation about what God was doing at Calvary 2000 years ago. Garry Williams has written a few articles recently that I found very useful when defending the penal and substitutionary nature of Jesus' death in a Theology essay last year, and Jim Packer's RTSF monologue What did the Cross achieve? is a classic work of recent years. But I can't think of such a systematic study of the biblical texts, the history of the doctrine, and the common ways in which penal substitution is called into question that has been quite so extensive. I hope in fifty years, God willing, I'll have a well-worn and much-prized copy of this on my bookshelf.
You can read John Piper's foreword on the book's site here, but here's a snippet that caught my eye:
There was only one hope for me – that the infinite wisdom of God might make a way for the love of God to satisfy the wrath of God so that I might become a son of God.
This is exactly what happened, and I will sing of it forever. After saying that I was by nature a child of wrath, Paul says, ‘But God, being rich in mercy, because of the great love with which he loved us, even when we were dead in our trespasses, made us alive together with Christ’ (Eph. 2:4-5 ESV). What a grievous blindness when a teacher in the church writes that the term ‘children of wrath’ cannot mean ‘actual objects of God’s wrath . . . [because] in the same breath they are described as at the same time objects of God’s love’. On the contrary. This is the very triumph of the love of God. This is the love of God – the ‘great love with which he loved us’. It rescued me from his wrath and adopted me into sonship.