15. Cultivate PEACE. Next to the blessing of peace with God and in our own conscience, is that of peace with our fellow men. “As much as lies in you, live peaceably with all men.” (Rom 12:18) And again, “Follow peace with all men.” (Heb 12:14) The real source of all the wars, contentions, and disturbances which are in the world, is the pride, the envy, the covetousness, and other evil passions of our nature. Eradicate these, and in their place introduce pure and kind affections, and you will experience a double peace—peace within, and peace with others.
Every Christian temper is friendly to peace. I know, indeed, that Christ says that He came not to bring peace but a sword. But He refers not to the nature of His religion—but to the reactions which He foresaw would occur from the perverse opposition of men—to that which is godly. The genuine spirit and tendency of the Gospel is beautifully and emphatically expressed in the angelic anthem, sung by the celestial choir at the nativity of our Savior—”Glory to God in the highest, and on earth peace, good will to men.” (Luke 2:14) All the adopted sons of God are sons of peace, and are peacemakers. “Live in peace,” says Paul, “and the God of peace shall be with you.” (2 Cor 13:11) Christian humility, meekness, and benevolence must, from the nature of the case, have a mighty influence in producing and maintaining peace. For, as the apostle Peter argues, “Who will harm you, if you be followers of that which is good”? (1 Pet 3:13)
No system was ever so well adapted to produce universal peace as Christianity, and the only reason why this effect has not followed its reception everywhere, is that its true tenor and spirit have not been imbibed. Just so far as this blessed system is cordially embraced, it cuts up by the roots all causes of contention, except that which has for its subjects, sin and error. It teaches us not only to love our friends and brethren, but also our bitterest enemies, to return blessing for cursing, and kindness for ill treatment. Endeavor then to cherish habitually those kind affections which lead to peace; and while you seek peace in your own souls, make it an object to promote peace in the world, and covet the blessedness which is pronounced to belong to peacemakers. Their high honor it is to be denominated “the sons of God”.
– Archibald Alexander; Counsels of the Aged to the Young (See here for more info)