True emotional control is only possible for a Calvinist. And, sure, she doesn’t have to know that she’s a Calvinist, but she certainly has to deal with her desires like one.
Quotidian emotional control issues typically concern not being happy what we have, or what we don’t have, or what we see that someone else has. Another way to say it is that those who can’t control their every-day feelings of discontent are guilty of breaking the 10th commandment: You shall not covet.
Moses recorded God’s prohibition which included some examples:
“You shall not covet your neighbor’s house, you shall not covet your neighbor’s wife, of his male servant, or his female servant, or his ox, or his donkey, or anything that is your neighbor’s.” (Exodus 20:17)
The preceding commands are also about one’s neighbor: don’t murder, don’t commit adultery, don’t steal, and don’t bear false witness, all of which behaviors directly affect your neighbor. But who does it hurt if the problem is just unfulfilled longing in your heart? It offends God.
The problem here is not simple disobedience, it is idolatry. The idol could be the “thing,” as in, you want the car (that’s just a modernized tangible example, it could be “anything” material or abstract or perceived) more than you want God, but it’s often more like the kind of idol of a different god than the one who didn’t give you the car. Of course you’d be guilty if you stole the car, but that would break the 8th commandment. You’re guilty of the 10th commandment if you won’t give thanks to God for not giving it to you.
In Ephesians Paul said that the countermeasure to sexual immorality and impurity and covetousness, which is idolatry, is to “let there be thanksgiving” (Ephesians 5:3-5). Giving thanks is perhaps the ultimate act of submission, not just accepting God’s sovereignty but appreciating it (like a Calvinist). We will not be ready for higher level lessons of emotional control without accepting the results of God’s elections–His election of your house, your relationships, your productivity, your wealth–by honoring God and giving Him thanks.
Our gratitude is not just the result of emotional control, it is the reins of it.