The contemporary idea that freedom is being mentally undisciplined and letting your thoughts, emotions, and desires run loose is a lie. To abandon mental discipline is to accept inner anarchy.
The thoughts that you welcome and allow to remain in your mind mold your emotions and desires into their image. We have the ability to discipline our thinking and to develop a healthy, happy mindset, but not without much focus and effort.
Mental discipline is only developed by hard work. It’s not a skill that we’re born with.
Mental discipline is a vital part of genuine self-care. It involves paying attention to your thoughts and rejecting the harmful ones.
Persistent mental discipline can help restore and repair your brain. The power of a disciplined brain can avoid much inner pain. Still, changing our thinking habits requires much mental discipline.
One reason we don’t want to understand people who see things differently than we do is that it requires much mental discipline. Perhaps that’s the same reason we lack self-understanding.

He that dwelleth in the secret place of the most High shall abide under the shadow of the Almighty. I will say of the Lord, He is my refuge and my fortress: my God; in him will I trust.
I have been working on committing Psalm 91 to memory and I am struck by how much the mindset you are talking about is embodied in that passage: a mind set, dwelling, abiding, lingering, constantly focused on Him finds healing and protection.
Awesome observation, Jon! Thanks for your comment and encouragement.