4:7

the peace of God: This refers to the calmness and tranquility of mind that result from a Christian’s precious relationship with Jehovah God. A Christian may enjoy this peace even in the face of turbulent and trialsome circumstances. “The peace of God” does not come through mere meditation or personal effort; rather, it is given by Jehovah God himself, “the God of peace.” (Php 4:9; Nu 6:26; Ps 4:8; 29:11; Ro 15:33; see study note on Ga 5:22.) Having “the peace of God” is dependent on having a close relationship with Jehovah and doing what is good in his eyes. (Pr 3:32) He gives his servants confidence that he knows their needs and situation and that he answers their prayers. Such assurance puts their heart and mind at rest.​—Ps 34:18; 94:14; 2Pe 2:9; see study note on will guard in this verse.

that surpasses all understanding: The peace of God cannot be attained through human reasoning or planning. In fact, greater “understanding” of a situation may lead to greater anxiety and hopelessness. (Ec 1:18) However, the peace of God “surpasses” anything that humans can imagine. A servant of Jehovah may not see a way out of his problems. While God may do the unexpected and rescue his servants from their trial (Mr 10:27; 2Pe 2:9), at times the only solution may be patient endurance (Jas 5:11). In such situations, Jehovah will always give peace to those who fully trust in him. (Isa 26:3) Those who do not know Jehovah cannot fully understand the tranquility and peace of mind that God’s people enjoy in the face of serious problems, physical harm, or even death.

will guard: The Greek verb for “guard” is a military expression. The literal idea could refer to a sentry or to a garrison of troops that was assigned to guard a fortified city. (2Co 11:32) Here and elsewhere in the Christian Greek Scriptures, it is used metaphorically. (Ga 3:23; 1Pe 1:5) Philippi was a military city. The inhabitants of Philippi slept peacefully, knowing that soldiers were guarding the gates of their city. In a similar manner, faithful Christians have “the peace of God” guarding their hearts and minds, so that they enjoy peace of mind and spiritual security. They know that Jehovah cares for them and wants them to succeed. (Ps 4:8; 145:18; 1Co 10:13; 1Pe 5:10) That knowledge guards them from becoming overwhelmed by anxiety or discouragement.​—See study note on the peace of God in this verse.

your hearts: When the term “heart” is used figuratively in the Bible, it often refers to the total inner person. However, when mentioned together with the mind, or “mental powers,” it apparently takes on a more specific meaning and refers mainly to a person’s emotions, desires, and motives.​—See study note on Mt 22:37.

your mental powers: Or “your minds; your thoughts.” The Greek word Paul here uses refers to a person’s intellect. It is rendered “minds” at 2Co 3:14; 4:4; 11:3 and “thought” at 2Co 10:5. By mentioning both “hearts and . . . mental powers,” Paul emphasizes that “the peace of God” guards a Christian’s entire inner person.

by means of Christ Jesus: Christians can receive the peace that God gives only if they have faith in Jesus and understand his role in fulfilling God’s purpose. This is because Jesus’ ransom sacrifice opens the way to forgiveness of sins, which makes possible a close personal relationship with Jehovah. This relationship is the basis for true peace of mind and heart. (Ac 3:19; Ga 1:3-5; 1Jo 2:12) Christians can also draw comfort from remembering that as King of God’s Kingdom, Jesus will undo any damage Satan and his system may inflict. (Isa 65:17; 1Jo 3:8; Re 21:3, 4) Additionally, Jesus promised to be with his disciples, actively supporting them even through the last days of this system. This contributes to their peace of mind.​—Mt 28:19, 20; Php 1:18, 19.