The similar phrase 'Worldly Christianity' is one used by Bonhoeffer. It's J Gresham Machen that I want to line up most closely with. See his Christianity and culturehere. 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.
We travelled today from Eldoret to Naruku. I had not realised that would involve crossing the equator but it did. First time standing on the equator line. (I have stood on the Greenwich meridian before now. To stand on both at the same time, you have to be on Null Island, somewhere out in the Atlantic.