We know that God himself is love (see the First Letter of John, especially 4:16). In order to understand love, a function of the intellect, and then to exercise it, a function of the will, we must look at this God who is love itself. We look at Jesus Christ to see the God who is love, and the way we as human persons are to exercise this love, for Jesus is true God and true man. He is the "reflection of the Father's glory, the exact representation of the Father's being" (Hebrews 1:3).
Our Lord tells us clearly that He has loved us as the Father loves him, and He desires us to live on in his love. He clarifies the point, knowing that we are slow to understand at times. "You will live in my love if you keep my commandments" (John 15:10). The New Covenant clearly did not abolish the Old Covenant; rather, it brought it to fulfillment (See Mt. 19:16-19). The Ten Commandments are still there for us, as the Catechism of the Catholic Church teaches: "Since they express man's fundamental duties toward God [love] and towards his neighbor [love], the Ten Commandments reveal, in their primordial content, grave obligations. They are fundamentally immutable, and they oblige always and everywhere. No one can dispense from them. The Ten Commandments are engraved by God in the human heart.
There has been a notion in recent years that implies that somehow the Commandments are an affront to our freedom or dignity as humans. Nothing could be further from the truth. The fact of the matter is that the infinite wisdom who is our provident and loving Father gave us the commandments to set our freedom free, and to insure we live in accordance with our human dignity.
Some of us think that the precepts laid down by God and his church are humanly impossible to keep. We cannot of our own diminished and impoverished power keep the Commandments as perfectly as the holiness of God and our creation in the image and likeness of God demands. We are in need of help to do this. We have the help. This is the reason Jesus assumed a human nature and became like one of us in everything except sin. This is the reason for the Paschal Mystery--the mystery of love.
God's grace provides the power to obey the Commandments, hence to love, and to live a truly human and truly Christian existence. God's grace provides the light to see the authentic answers to people's questionings about the meaning of love, of human life, activity, and death:
The most perfect answer to these questionings is to be found in God alone, who created man in his own image and redeemed him from sin; and this answer is given in the revelation in Christ his Son who became man. Whoever follows Christ the perfect man becomes himself more of a man (Vatican II, Gaudium et Spes, 41).
We must use the means God has given us for acquiring his grace: the seven sacraments, especially the sacraments of reconciliation and the Eucharist, prayer and penance, and the assiduous practice of all of the human and Christian virtues. If we do this the grace will be there for us, and indeed we'll have the power to love the Lord with all of our heart, mind, and strength, and to love our neighbor as ourself. Without making use of the means available, however, we should not wonder that we can't live and love as God and his church would have us do.
"Love one another as I have loved you. There is no greater love than this: to lay down one's life for one's friends. You are my friends if you do what I command you" (John 15:12-14). Authentic love involves sacrifice; it is essentially an act of the will. To imagine that love is primarily a feeling, an emotion, or a chemistry is a fatal error. This fallacious notion kills marriages before they ever come to life. If love is merely a feeling or emotion it is up one day and down the next, and that is not the kind of roller coaster ride God wills for his beloved children. Love is a decision, an act of the will. We will the highest and best thing for the sake of the beloved, even if, and especially if, it costs us dearly. That is the love of the Father. That is the love of his only Son who was sent "that whosoever would believe in him would not perish, but have eternal life." That is truly Christian and truly human love.
If we love each other as God has first loved us, we desire what God desires for us: eternal salvation. All else pales into utter insignificance when compared to this fundamental object of human existence. "If you gain the whole world, and destroy yourself in the process, what have you gained?" (See Mt 16:26, Mk 8:36, Lk 9:25). If a husband loves a wife, if a wife loves her husband, if they love their children, if a priest loves his people, etc., then they not only desire the highest and best good for the sake of those they love, but they will do anything and everything possible to bring this about. We must put on the mind of Christ, the mind of a savior. Love in the end always entails self-sacrifice.
In this age of self-assertiveness, in this day of "looking out for number one," and in an ego-centric age this is a mighty challenge to be met head on by Christians. Do we love enough to embrace the cross in our life? Will we suffer any and all things in order to guard and guide those we love to paradise? Will husbands put their wives and children first? Will wives do the same? Will priests pray and do penance for their people--suffer for them? Will we embrace the cross for each other? Will we order our entire lives in the best interest of the salvation of souls, especially the souls of our own loved ones?
Living a holy and upright life involves having enough humility to obey God's Commandments and the precepts of his Church, and it involves helping others to do so as well. "The servant is no better than the Master," (See Matthew 10:24-25, John 13:16, 15:20). The Master said "where I am, there my servant will be" (See John 12:26). It was necessary that He be "lifted up from earth" in order to "draw all men to myself" (See John 12:32). It is necessary for us to enter into the self-donating love of Christ in order to likewise draw our loved ones to Jesus, and through him to the Father.
Indeed, "There is no greater love than this: to lay down one's life for one's friends."