This book by Stephen Westerholm is a nice hundred page piece debunking the new perspective and showing that Luther had it basically right about Paul while Stendahl and others are mistaken. He has a much bigger book saying similar things (Perspectives old and new on Paul). The book is very good at sticking to its task and sets things out very well. Westerholm is the author of a number of books that look very interesting (see here).
Bonhoeffer uses a similar phrase 'worldly Christianity'. It's J Gresham Machen that I want to line up most closely with. See his Christianity and culture here. Having done commentaries on Proverbs (Heavenly Wisdom) and Song of Songs (Heavenly Love), a matching title for Ecclesiastes would be Heavenly Worldliness. For my stance on worldliness, see 3 posts here.