Kenneth Grahame (1859 – 1932) was a Scottish writer. He is most famous for The Wind in the Willows (1908), one of the classics of children's literature. I've read that and indeed it has been hard to escape it in one form or another. He also wrote a book with a chapter called The Reluctant Dragon which is apparently a Disney film but I've not seen it.
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.