William Carey (1761 – 1834) was an English Particular Baptist pioneer missionary, known as the "father of modern missions." He was one of the founders of what became the Baptist Missionary Society. As a missionary in Serampore, India, he translated the Bible into Sanskrit, Bengali and numerous other languages and dialects. His sermon calling for overseas mission work has become famous through its two heads - Expect great things from God, Attempt great things for God (note the order). Carey was an amazing phenomenon. He left school at 14 to be apprenticed as a cobbler but today at least nine schools are named after him.
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.