We had a very nice family day out last Saturday at the Geffrye Museum of the home in East London. The free museum presents a series of home scenes from 1630 to the present day and at this time of the year has a Christmas theme although that hardly kicks in until the Vicorian period. It was a very interesting set up and would be worth a second visit I'm sure. There is a nice gallery 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.