God Alone Tests the Hearts of Men

Jonathan Edwards in The Distinguishing Marks of a Work of the Spirit of God, Section III: Practical Inferences:

“There was a time when I did not imagine that the heart of man was so unsearchable as it is. I am less tolerant and less intolerant than once I was. I find more things in wicked men that may be counterfeit, even when they make a fair show of piety. I find more ways that the remaining corruption of the godly may make them appear like carnal men, formalists, and dead hypocrites than once I knew of. The longer I live, the less I wonder that God keeps it as His right to try the hearts of the children of men.”

Quoted in The Spirit of Revival: Discovering the Wisdom of Jonathan Edwards (Crossway)