Peaceis a word with different meanings in the bible.
In the Old Testament, peace means completeness, soundness, and well-being of the total person. This peace was considered God-given, obtained by following the Law (Ps. 119:165). Sometimes, peace had a physical meaning, suggesting security (Ps. 4:8), contentment (Is. 26:3), prosperity (Ps. 122:6-7) and the absence of war (1 Sam. 7:14). The traditional Jewish greeting, shalom, was a wish for peace.
In the New Testament, peace often refers to the inner tranquility and poise of the Christian whose trust is in God through Christ. This understanding was originally expressed in the Old Testament writings about the coming MESSIAH (Is. 9:6-7). The peace that Jesus Christ spoke of was a combination of hope, trust, and quiet in the mind and soul, brought about by a reconciliation with God. Such peace was proclaimed by the host of angels at Christ's birth (Luke 2:14), and by Christ Himself in His SERMON ON THE MOUNT (Matt. 5:9) and during His ministry. He also taught about this kind of peace at the Lord's Supper, shortly before His death (John 14:27).
The apostle Paul later wrote that such peace and spiritual blessedness was a direct result of faith in Christ (Rom 5:1).
(Source: Nelson's Illustrated Bible Dictionary, Thomas Nelson Publishers, New York, P. 813)
 What in your mind defines peace? Ans - Blessed assurance and the absence of conflicts.
 What aspect in your life would you need peace the most? Ans - While things like personal relationship, work pressure, financial decisions could no doubt steal my joy and peace, I learned that God will eventually work things out for me. I simply trust and obey, and I shall do my best in the meantime.
 How would you live peacefully and sleep well? Ans - I sleep well most of the time, as I learn to trust in Jesus, knowing that my life is always under God's perfect control. For instance, immediately after I survived a life-threatening auto-accident 15 years ago, I truly felt the tranquility and assurance in God's protection. I sensed that my life is not done yet on this earth. And God will take care of me with my best interest.