In comparing different aspects of peace it is helpful to note that in John 14:27, the Lord distinguishes between peace left to us and peace given to us. "Peace I leave with you” is peace with God as to every question of sin. He made peace by the blood of His cross, and brought the news of it on the day of His resurrection when He stood in the midst of His own and greeted them with “peace be unto you.” He showed them His hands and side as witness of the work by which peace was accomplished, and commissioned them to go forth with it to others. (John 20:19-21). It was the precious legacy of His death. (We have it in Romans 5:1 as we believe the testimony of God to the facts of His having been delivered for our offences and raised again for our justification.) It is peace of conscience. He never needed it: we did, and He made it and left it to us.
But the Lord goes on to speak of a deeper character of peace - “My peace I give onto you”. It is the peace in which He ever walked with the Father; the calm unruffled peace afforded by resting in His love and submitting Himself completely to all His ways. He characterizes it as His, and gives it to be ours absolutely - not as the world gives indeed (for though it may give largely and generously it gives away) but as bringing us into possession of it with Himself. This principle is here applied to His peace but is true of all he gives: His joy (John 15:11), His glory (John 17:22) and the place He has in His Father’s love (John 17:23, 26). This second peace, coming in its perfect order, is peace of heart; of the heart that has found the resting place of Christ as its own in a Father’s love well known. We are entitled to count it ours - by His absolute gift - and to live in it practically through all the stress and strain of circumstances. Once again it is formally referred to in Colossians 3:15: “Let the peace of Christ rule in your hearts” holding its blessed sway in all that is there, “to which ye have been called in one body,” and thus in all our relations with our fellow-Christians.
The Peace of God
It only remains to emphasize the strongly conditional character of the peace promised in Philippians 4. But the only condition is that we trust God with what would burden us, putting the care upon Him instead of carrying it as a weight upon our hearts. It is not now the peace of Christ who as man passed through the scene of trial but the peace of God on the throne where no breath of trial ever came that He guarantees shall keep our hearts and minds. And if our poor hearts would say that it is utterly incomprehensible, God has anticipated and tells us that it “passeth all understanding.” He does not expect us to understand it, but by acting upon His word in simple confidence of heart in Him we shall realize the truth of it. May it be ever more and more with us.