I wanted to ask Calvinists, especially well read ones, what apart from Calvin's concept of predestiny are his most loved and greatest insights?
One of Calvin's greatest insights was realizing how insightful Augustine could be.
Calvin loved him some Augustine.
I really like Calvin's use of
divinitatis sensum. "There is within the human mind, and indeed by natural instinct, an awareness of divinity" (ICR I.III.I). Somewhat like our five senses, we have a sense for divinity, which he also refers to as the "seed of religion." That was new to me when I read Calvin. I think this is why religion is ubiquitous throughout human history. And, I think something like a sense for the divine is what ensures that if we seek, we will find. It is built into our DNA, perhaps, to seek God and find God. I wouldn't argue for the DNA bit, but I think God has created us the know God so it makes sense, divine sense even.
I also like Calvin's image of a nurse or mother speaking baby talk to an infant to describe God's transcendence and how we should think of the anthropomorphic metaphors and mental images used for God in the scriptures.
"For who of even slight intelligence does not understand that, as nurses commonly do with infants, God is wont in a measure to "lisp" in speaking to us?" (ICR I.XIII.I)
God speaks baby talk to us, which I take to mean we should not take ourselves and our positions as seriously as Calvin did.