I sometimes get hooked on a song. Currently it's the subtle and mesmerising post-Akkerman track Mobilea by the Dutch band Brainbox. Here is a live version from last year featuring Rudy de Queljoue and Jan Schuursma on guitars with the world's greatest drummer Pierre Van Der Linden. Singer Kaz Lux makes the introduction.
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.