I understand humility ultimately to be acceptance of reality, while pride is a kind of spiritual psychosis, or break from reality. The proud person places themselves (or someone else, like a parent, spouse or child) at the centre of the universe. The humble person recognizes – and embraces – their true place in reality, and God’s place at the centre. And having given up their claim to the throne, the humble person is free and happy and at peace. This is at odds with our usual view of humility, which we confuse with self-deprecation. Lewis said it best:
Do not imagine that if you meet a really humble man he will be what most people call ‘humble’ nowadays: he will not be a sort of greasy, smarmy person, who is always telling you that, of course, he is nobody. Probably all you will think about him is that he seemed a cheerful, intelligent chap who took a real interest in what you said to him. If you do dislike him it will be because you feel a little envious of anyone who seems to enjoy life so easily. He will not be thinking about humility: he will not be thinking about himself at all. (Mere Christianity, book II, chapter 8)
Applying this definition to God, could God be proud? For Him, psychosis would be to not place Himself at the centre of the universe! However, having done that, He is therefore free to take the lowest place (Phil 2:5-11), to take care of good people and evil people (Mt 5:45), to love His enemies (Rom 5:8) and remain faithful to the faithless (2Tim 2:13). So it is only God’s unyielding grip on reality that makes His mercy possible.
So then, how does God react when humans take credit for His work? The classic term for this is vainglory, or vainly taking credit for (glorying in) that which was not primarily due to your own efforts. For example, being proud of your good looks is actually vainglory – sure you take care of yourself, but your starting point was winning the genetic lottery. Being proud of your career success is likewise vainglorious – sure you worked really hard, but you got some good breaks, but many others work just as hard (if not harder) and don’t achieve the same reward. And where did that capacity to work hard come from in the first place, hmm?
But how does God feel about our vainglory? I think He has conflicting emotions (can we imagine that?). First, I think he is delighted that His purposes are being achieved, even if they are being done in our own name (Phil 1:17-18); because He is free to take the lowest place, He is unbothered about getting the credit. Second, I think God is amused, the way we are when a small child boasts of how tall they are when sitting on our shoulders. Finally, God weeps for us, as our vainglory is blinding us to reality – and that psychosis is making our lives, and the lives of those around us, a living hell. That is what stirs Him on occasion to break in with reality, even when it threatens to break us (see Dan 4:28-37) – the stakes are that high.