I wouldn't say "low opinion" or "pessimistic view". Rather I would call it a realistic assessment. All one has to do is be honest with themselves in relationship to how much they like to read of God's word, how much they like to pray, or even how much they like to tithe (to name but a few things). If one takes an honest appraisal of themselves, the depths of our sinfulness becomes readily apparent.
But it's a funny thing. The more we understand about and admit to our sinfulness, the more we understand the depths of the love of God.
Well said.
Peace be with you
Calvin presents human nature as very nearly corrupt, so much so that he saw very few passing through the narrow gate. We tend to forget the apocalyptic nature of much reform thinking at the time. Think of the anabaptists et al. Plague and war and the corruptions in the Church. The Sultan right at the door of Christendom. The Emperor at war with his princes. And, yes, if you look at the behavior of ordinary men. Not a pretty picture, especially as seen through the eyes of a fanatic like Calvin, or one like Loyola. Calvin’s intellect made him indeed more realistic than the duller blades. He seems personally not to have cared a flip about the forms of ecceciology, or even liturgy, and less inclined to iconoclasm. If he was puritan, it was one more like Cotton Mather. But his notions of justice and mercy are too Mohammedan for me.