Answer
Most people would define peace of mind as the absence of mental stress and anxiety. The expression “peace of mind” conjures up images of Buddha-like composure wherein calm, comfort, and composure are so prevalent that nothing can disturb the one who has peace of mind. An imperturbable, placid person is said to have peace of mind. The only time “peace of mind” is found in the Bible is the NIV translation of 2 Corinthians 2:13 where Paul says he found no “peace of mind” because he didn’t find Titus in Troas. The literal translation of this phrase is “rest of my spirit.”
The Bible uses the word peace in several different ways. Peace sometimes refers to a state of friendship between God and man. This peace between a holy God and sinful mankind has been effected by Christ’s sacrificial death, “having made peace through the blood of his cross” (Colossians 1:20). In addition, as High Priest the Lord Jesus maintains that state of friendship on behalf of all who continue to “come to God by him, seeing he always lives to make intercession for them” (Hebrews 7:25). This state of friendship with God is a prerequisite for the second kind of peace, that which sometimes refers to a tranquil mind. It is only when “we have peace with God through our Lord Jesus Christ” (Romans 5:1) that we can experience the true peace of mind that is a fruit of the Holy Spirit, in other words, His fruit exhibited in us (Galatians 5:22).
Isaiah 26:3 tells us that God will keep us in “perfect peace” if our minds are “stayed” on Him, meaning our minds lean on Him, center on Him, and trust in Him. Our tranquility of mind is “perfect” or imperfect to the degree that the “mind is stayed on” God rather than ourselves or on our problems. Peace is experienced as we believe what the Bible says about God’s nearness as in Psalm 139:1-12, and about His goodness and power, His mercy and love for His children, and His complete sovereignty over all of life’s circumstances. But we can’t trust someone we don’t know, and it is crucial, therefore, to come to know intimately the Prince of Peace, Jesus Christ.
Peace is experienced as a result of prayer. “Be anxious for nothing, but in everything by prayer and supplication, with thanksgiving, let your requests be made known to God; and the peace of God which surpasses all understanding, will guard your hearts and minds through Christ Jesus” (Philippians 4:6-7).
A peaceful mind and heart are experienced as a result of recognizing that an all-wise and loving Father has a purpose in our trials. “We know that all things work together for good to those who love God and are called according to His purpose” (Romans 8:28).
God can bring a variety of good things, including peace, from the afflictions that we experience. Even the discipline and chastening of the Lord will “yield the peaceable fruit of righteousness” in our lives (Hebrews 12:11). They provide a fresh opportunity for “hoping in God” and eventually “praising Him” (Psalm 43:5). They help us “comfort” others when they undergo similar trials (2 Corinthians 1:4), and they “achieve for us an eternal glory that far outweighs them all” (2 Corinthians 4:17).
Peace of mind and the tranquility of spirit that accompanies it are only available when we have true peace with God through the sacrifice of Christ on the cross in payment of our sins. Those who attempt to find peace in worldly pursuits will find themselves sadly deceived. For Christians, however, peace of mind is available through the intimate knowledge of, and complete trust in, the God who meets “all your needs according to his glorious riches in Christ Jesus” (Philippians 4:19).