If I were asked to sum all of Christian faith in a single word, I would answer, “Love.” Love is the center of Christian faith, ethics, understanding, and life. As St. John the Theologian tells us in his first epistle “God is love” and only those who know love know God (4:8). St. Paul tells us in Romans that if we love others, we have fulfilled the Law of God:
8 Owe no one anything except to love one another, for he who loves another has fulfilled the law. 9 For the commandments, “You shall not commit adultery,” “You shall not murder,” “You shall not steal,” “You shall not bear false witness,” “You shall not covet,” and if there is any other commandment, are all summed up in this saying, namely, “You shall love your neighbor as yourself.”10 Love does no harm to a neighbor; therefore love is the fulfillment of the law.
To understand Christianity, to understand the most holy Trinity, to understand our faith’s ethical commandments, we must look always through the lens of love. Without love we walk in darkness, blundering and lost, but with love we walk in light with Christ as our guide.
St. John Chrysostom outlined beautifully some of the practical effects of true Christian love acting in the world in his 32nd homily on 1 Corinthians:
Wherefore also He saith to Peter, “If thou lovest Me, feed My sheep.” (John 21:16.)
And that ye may learn how great a work of virtue [love] is, let us sketch it out in word, since in deeds we see it no where appearing; and let us consider, if it were every where in abundance, how great benefits would ensue: how there were no need then of laws, or tribunals or punishments, or avenging, or any other such things since if all loved and were beloved, no man would injure another. Yea, murders, and strifes, and wars, and divisions, and rapines, and frauds, and all evils would be removed, and vice be unknown even in name. Miracles, however, would not have effected this; they rather puff up such as are not on their guard, unto vain-glory and folly.
Wherefore, having said, “The first and great commandment is, Thou shalt love the Lord thy God,” he added, “and the second—(He leaves it not in silence, but sets it down also)—is like unto it, Thou shalt love thy neighbor as thyself.” And see how with nearly the same excellency He demands also this. For as concerning God, He saith, “with all thy heart:” so concerning thy neighbor, “as thyself,” which is tantamount to, “with all thy heart.”
Yea, and if this were duly observed, there would be neither slave nor free, neither ruler nor ruled, neither rich nor poor, neither small nor great; nor would any devil then ever have been known: I say not, Satan only, but whatever other such spirit there be, nay, rather were there a hundred or ten thousand such, they would have no power, while love existed. For sooner would grass endure the application of fire than the devil the flame of love. She is stronger than any wall, she is firmer than any adamant; or if thou canst name any material stronger than this the firmness of love transcends them all. Her, neither wealth nor poverty overcometh: nay, rather there would be no poverty, no unbounded wealth, if there were love, but the good parts only from each estate. For from the one we should reap its abundance, and from the other its freedom from care: and should neither have to undergo the anxieties of riches, nor the dread of poverty.
Therefore Paul saith, that the love which we are speaking of is the mother of all good things, and prefers it to miracles and all other gifts. For as where there are vests and sandals of gold, we require also some other garments whereby to distinguish the king: but if we see the purple and the diadem, we require not to see any other sign of his royalty: just so here likewise, when the diadem of love is upon our head, it is enough to point out the genuine disciple of Christ, not to ourselves only, but also to the unbelievers. For, “by this,” saith He, “shall all men know that ye are My disciples, if ye have love one to another.” (John 13:35.) So that this sign is greater surely than all signs, in that the disciple is recognized by it.
Such is a world ruled by Christian love. It is a world without wealth or poverty, without rulers and laws, without oppression, injustice, or violence. In short it is the Kingdom of God. It is a far cry from the world in which we live, because to our shame, too few Christians practice Christian love. We are easily beset by our own daily cares, by personal differences, by sectarianism, and strife. Often we fail even to show our dearest loved ones true Christian love. We are imperfect creatures in an imperfect world, but Christ gave us his example of perfect love and perfect humanity. It is our duty as Christians to follow his example, to love everyone with our whole hearts, to love even to hardship and death. Only by giving of ourselves to our neighbor, to the destitute, to our enemies, can we put an end to suffering and sin. Only by giving of ourselves can we hope to be worthy of the Kingdom of Heaven. Only by giving of ourselves can we express our love for God and His creation just as God expressed His love for us when He became flesh in the person of Jesus of Nazereth, was crucified, and then raised Himself from the dead, thus freeing us from death. Let us not merely love in word or in tongue, but let us love in deed and in truth, for St. John wrote:
20 If someone says, “I love God,” and hates his brother, he is a liar; for he who does not love his brother whom he has seen, how can he love God whom he has not seen? 21 And this commandment we have from Him: that he who loves God must love his brother also. (1 John 4)