As it happens I dipped during this week into one of the (IMO) great books of modern biblical scholarship, Francois Bovon's Luke The Theologian (Second Revised Edition, Baylor Press). If I went to a publisher and said, "Look, I have read everything there is to read on Luke and Acts and I would like to give a report on that reading," I suppose the publisher would show me the door. But Bovon manages to do just that with brilliant energy which takes the reader on a journey into hidden nooks and crannies in the journey which is Luke the theologian using history as a vehicle to set out christology, missiology, soteriology, ecclesiology and pneumatology.
Relating to PSA, something I learned this week is an insight of Charles Moule about preaching in Acts. Bovon's whole paragraph is this:
"Finally, if the expiatory virtue of the death of Jesus does not appear except in Acts 20 it is because of the literary genre of Luke's texts and the editor's theological reticence. It was not usual in early Christianity to underscore the salvific power of the cross in the sermon. Rather, this was done in the catechism. This is why the hyper emon [i.e. Christ died for our sins] appears in the Epistles, reflecting a catechism, and in the sole speech in Acts addressed to Christians (Acts 20:28 [...the church ... which he obtained with his own blood])." [p. 175]Sometimes scholars worry about the differences between Luke's theology and Paul's theology, precisely because if Paul is the great hero in Acts then that begs the question how Luke could get Paul so wrong. A particular difference is the seeming lack of a theology of the cross - the centre of Pauline theology - in Luke's writings, especially in Acts.
I understand Moule (via Bovon) as saying that an explanation for the difference is that Paul's writings are catechetical - instructional for Christians - whereas most sermons in Acts are evangelistic with a non-Christian audience.
In relation to the atonement as a specific subject for preaching and teaching, Moule via Bovon is saying that it is missing in Acts where we would expect it to be missing, in the proclamation of the gospel, and present where we would expect it to be present, in instruction to Christians.
So, here is an intriguing possibility: the apostles did not proclaim atonement (let alone penal substitutionary atonement) in their preaching of the gospel, but they did teach atonement in their instruction of Christian disciples.
Should we follow their example?
*I acknowledge that some would say there is a 'doctrine of atonement' but not a 'doctrine of penal substitutionary atonement', rather within the doctrine of atonement PSA is a model or one understanding of 'how' atonement 'works'. I also acknowledge that although the case is made (particularly by evangelicals) that the ancient fathers taught atonement in such a way that PSA was front and centre of their understanding, we do not find the phrase' penal substitionary atonement' in their teaching (as far as I know) and thus a list of 'doctrines the ancient fathers taught' is unlikely to include 'the doctrine of penal substitutionary atonement.' However, in my view, PSA is a distinctive doctrine within the doctrines or teachings which evangelicals both wish to make the case for within Christian discourse and to acclaim as a distinctive doctrine relating to definition of the 'evangelical' movement within Christianity. Putting that another way, an evangelical is distinguished from those not wishing to so identify themselves by virtue of commitment to PSA.