Come unto me all ye that labor, and are laden, and I will ease you. Take my yoke on you, and learn of me, for I am meek, and lowly in heart: and ye shall find ease unto your souls. For my yoke is easy, and my burden is light. ... He answered them saying: the evil and advoutrous generation seeketh a sign, but there shall no sign be given to them, but the sign of the prophet Ionas. For as Ionas was three days, and three nights, in the whale's belly: so shall the son of man be three days and three nights in the heart of the earth. ... Again, the kingdom of heaven is like unto a merchant, seeking good pearls, which when he had found one precious pearl, went and sold all that he had, and bought 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.