"Keep thy heart with all diligence; for out of it are the issues of life." -Proverbs 4:23
Set a watch at your mind. If you are to have any peace, and any joy, then you must focus your attention on things above and not on things of this earth.
In the world we will have tribulation, but Jesus overcame the world. And, those who look to Him, have peace. His peace is not like the world's peace; a peace that is predicated on external circumstances, but a peace that surpasses all understanding.