There is a very old Christian doctrinal term, which is hard to understand and needs some up-dating: impassibility. Have you ever heard it? I only began interacting with it a couple of years ago. It's important, because it's about God.
The word "impassible" comes from the Latin passionem, later changed into passio, taking over for the Greek word pathos. The word "impassible" did not mean that the person was empty of all sentiment, though the word has turned into that for some writers. The word speaks of suffering. For example, Christians speak of Christ's "passion" week, the week that led up to His crucifixion.
The word passio can refer to what we might call "irrational gut impulses", like blinding rage. The virtuous person's goal was to act from noble affections, not those kinds of gut instinct.
In popular use, the word "passion" has watered-down to a mere synonym for "lust." There used to be a daytime drama named Passions, in which characters acted out their various lusts. Or, people speak about their "passion" for music, or some other intense enthusiasm. Their emotions become inflamed by overpowering desire.
Reclaiming the original meaning of the word sheds light on what kind of Person God is. There's comfort and warning to be found from the fact that God is impassible.
First, God can't suffer. Passio refers to suffering so that means God can't suffer.
He can't suffer physically, because He is purely a Spirit (John 4:24). He doesn't age. He can't get sick. He can't die. He is all-knowing and all-wise, Isaiah 40:28, so nothing surprises Him. God is perfectly righteous (Psalm 145:17), so He never suffers from sin's psychological effects or sin's practical consequences. He is all-powerful, so even if anything might make Him suffer, He could stop it!
"What about Jesus?", you might ask. Jesus of Nazareth suffered, because He was (and is) a human being. Christ was eternal God the Son united to a fully human nature (body and soul), minus the sin. Classical Christian doctrine teaches that Christ's human nature suffered while on the earth, therefore Christ the person suffered. But He was one person with two natures. His divine nature, because it was divine, did not suffer. (For more study on that, I refer you to the Creed of Chalcedon.)
We should be thankful that Christ in His human nature suffered, because that makes Him our sympathetic high priest. But we should also give thanks that God, in His essential eternal nature, cannot suffer, because people make terrible mistakes when they're suffering. Their judgment becomes impaired, and their abilities can become disabled. God is never in any danger of either thing happening.
Second, God never acts out of "irrational gut impulses."
Aren't you glad? How many mistakes have you made because, in a moment, you felt driven to say or do something that in hindsight you know was very foolish? God never, ever does that.
God is only wise (Romans 16:17); there's no foolishness in God at all. Everything God has ever done was directed by His wisdom (Psalm 104:24). And every bit of God's wisdom eternally springs up from within Himself -- He doesn't need to learn anything from universe He created (Isaiah 40:13). No one advises God. He advises everybody else!
Third, God's emotions are clean and free of sin.
It is clear from the Bible that God experiences emotion. Some Christian theologians in some circles deny this, on the basis that God doesn't change ("immutability"). Since emotion reflects a psychological change, therefore God doesn't really experience emotions. I think this confuses categories. God's essential nature doesn't change, but His interactions with people in time reveal different aspects of His character. Extrapolating ideas about God too far out from God's eternality is speculative and dangerous.
The Bible depicts God as expressing sentiments (affection, friendship, wrath, regret). Any teaching that leads us to say, "Well, the Bible only seems to say that" is dangerous, because there's no end to doing that. You could deny everything in the Christian faith using that approach.
We certainly should say that it's mysterious how the eternal God can already know all that will be, or could be, but still sincerely interact with us in each moment. God is eternal, and God is with us, at the same time. No one but God can interact with the world in that way.
We should say that God's emotions are just like ours, and yet very much unlike ours, in different ways. God is other, but God is not wholly other.
We should say that God's essential, perfect serenity is never disturbed, even when He says he regrets something, or is grieved (Genesis 6:6), or laments something (Deut. 5:29). God never experiences misery. His composure is invincible, even when He expresses displeasure.
God isn't just a giant projection of ourselves. God is different from us. Parts of God are unknowable. But the Bible is also clear that God isn't completely unknowable, or else we could not be saved (John 17:3).
So, give thanks that God has emotions, and give thanks that His emotions are pure, holy, untouched by sin or the tumultuous frailty of fallen flesh. God has righteous sentiments and affections, but He never experiences wrenching gut reactions, and is never impelled to unwise action.
God is impassible -- free from suffering, free from impulse, free from foolishness, free from sin, free from ignorance, free from every psychological weakness. This is why we can trust him, and rely on Him.