Although written more than eighty years ago J. Gresham Machen's opening words in his classic work Christianity & Liberalism still have a freshness and relevance about them. He wrote:
The purpose of this book is not to decide the religious issue of the present day, but merely to present the issue as sharply and clearly as possible, in order that the reader may be aided in deciding it for himself.
He knew that light is not always a welcome intruder in the church:
Clear cut definition of terms in religious matters, bold facing of the logical implications of religious views, is by many persons regarded as an impious proceeding.
In this regard it is quite clear that penal substitution has become a doctrine over which self-identifying evangelicals have quarreled. Not that calling yourself an evangelical gives you the right to jettison doctrines that are, and have always been, recognizably evangelical. But that has not deterred the attacks being made from within evangelicalism from academics and well known leaders, as well as those from the label-overlapping emerging church conversation.
And it is a great irony that many of the arguments leveled against penal substitution were those made a few centuries back by the Socinians. Faustus Socinus revised the doctrines of classic Western Christianity, and Reformed orthodoxy, right across the board. And he virulently opposed penal substitution. Perhaps the rehabilitation of his views under the evangelical banner, not through his writings or personal influence but by a corresponding orientation of the heart to the truths that he opposed, illustrates just how anti-reformational the movement has become.
And so let me give you a lengthy quotation from Pierced for our Transgressions that sets out the logical implications of the debate over penal substitution. Over a third of the book is given over to polemics. The authors have listed every objection to penal substitution that they could find, have supported these objections with quotations from contemporary authors (Green, Baker, Chalke, Mann, Fiddes, McLaren etc.), and have written a response to each one.
The bottom line: If you love the truth you will not be able to avoid fighting for it. Theological pacifism is not an option.
"It seems that opponents of penal substitution are agreed on the magnitude of the issue. They contend that penal substitution is an unbiblical view of the cross without support in the historic church. They claim that penal substitution undermines the doctrine of the Trinity, without which Christianity would not be Christianity at all. More than that, they insist that penal substitution portrays God as an unjust tyrant, a vindictive child abuser, and a hypocrite who pays no regard to Jesus' foundational teaching about love. Finally, they have argued that penal substitution has disastrous pastoral consequences, that it has been used to justify violence against women and children, and that it is stifling the mission of the church in the world. All of these accusations have been made in recent years...
These charges are extremely serious. We cannot pretend that critics of penal substitution are raising a minor point of dispute: they are accusing us of propagating a theological novelty, imposing our twisted modern world views on God's holy word, unwittingly encouraging and justifying sadistic acts of violence, and worshipping a malevolent, hypocritical deity who bears no resemblance whatsoever to the loving God of the Bible. Disagreements over penal substitution are fundamental; they cannot be ignored.
Of course, this does not mean Christian churches and organisations ought to divide at the first of disagreement on this issue. On the contrary, Christian love requires patient listening and discussion. However, if those who impugn penal substitution refuse to reconsider their position, there comes a time when we have no alternative but to part company. For the critics are right in this: differences over penal substitution ultimately lead us to worship a different God and to believe a different gospel."
Jeffrey, Ovey, Sach, Pierced for our transgressions, p. 216-7