So I'm listening to a recording of Carl Trueman on Bernard of Clairvaux and he begins "On Courtney Love ... see the chapter ... on Courtney Love". He's a hip guy, I guess, so I wasn't too phased and I soon cottoned on that he was actually talking about courtly love, of course. Still going deaf.
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.