Great peace have they who love God's law; nothing shall offend them or make them stumble (Psalm 119:165). He will guard you and keep you in perfect and constant peace as your mind (both its inclination and its character) is stayed on Him, when you commit yourself to Him, lean on Him, and hope confidently in Him. So trust in the Lord (commit yourself to Him, lean on Him; hope confidently in Him) forever, for the Lord God is an everlasting Rock (Isaiah 26:3,4).
Do not fret or have any anxiety about anything, but in every circumstance and in everything, by prayer and petition, with thanksgiving, continue to make your wants known to God. And, God's peace which transcends all understanding shall mount guard over your heart and mind in Christ Jesus (Philippians 4:6,7). For God did not give you a spirit of timidity, but He gave you a spirit of power and of love, and of calm and well-balanced mind and discipline and self-control (II Timothy 1:7).
If possible, as far as it depends on you, live at peace with everyone. Never avenge yourself, but leave the way open for God's wrath; for it is written, “Vengeance is Mine. I will repay,” says the Lord. But if your enemy is hungry, feed him. If he is thirsty, give him drink; for by so doing you will heap burning coals upon his head. Do not let yourself be overcome by evil, but overcome (master) evil with good (Romans 12:18-21). The effect of this righteousness will be peace (internal and external), and the result of this righteousness will be quietness and confident trust forever (Isaiah 32:17).
And thus, may your mouth always speak, “Lord, my heart is not haughty, nor my eyes lofty; neither do I exercise myself in matters too great for me. Surely, I have calmed and quieted my soul; like a weaned child with his mother, like a weaned child is my soul within me (ceased from fretting)(Psalm 131:1,2). In peace, I will both lie down and sleep, for You, Lord, alone make me dwell in safety and confident trust (Psalm 4:8).”