You keep him in perfect peace whose mind is stayed on you, because he trusts in you. Trust in the LORD forever, for the LORD GOD is an everlasting rock. (Isaiah 26:3–4)
What lasts? What endures? You don't have be a student of history to know that beliefs and institutions which once looked as if they would last forever in fact come crumbling down. The Ottoman Empire came and went, the Soviet Union collapsed and even Woolworth’s is gone.
If you live through these changes, it can be unsettling and even the month by month changes to Covid related regulations have been unsettling. Change may be constant, but that does not make it easier.
In the midst of the swirls of history, God stands as an “everlasting rock”. If you place your trust in him, then you find you have “perfect peace”. Why? Because you have a solid point on which to focus in the storms, a stable place in which to rest when all seems fluid. The testimony of the saints of old, and the saints of today, is that in the midst of difficulties they find that it is only God who can be a sure foundation for their life.
Keep your mind ’stayed’ on God, and you too will find him a sure and certain rock. Keep your mind stayed on God, and you will be able to join with David in proclaiming: “The LORD is my rock and my fortress and my deliverer, my God, my rock, in whom I take refuge, my shield, and the horn of my salvation, my stronghold.” (Psalm 18:2)