Some of my favorite Scriptures on peace:
Philippians 4:6-7 Don’t worry about anything, but in everything, through prayer and petition with thanksgiving, let your requests be made known to God. And the peace of God, which surpasses every thought, will guard your hearts and minds in Christ Jesus.
John 14:27 Peace I leave with you. My peace I give to you. I do not give to you as the world gives. Your heart must not be troubled or fearful.
2 Thessalonians 3:16 May the Lord of peace Himself give you peace always in every way. The Lord be with all of you.