I know that we are to love God with our whole heart, but in practical terms what exactly does that mean?
That is a very good question, which, I am sure, many people ask. Is love for God feeling that we love him, is it telling him that we love him, or what?
First, we should remind ourselves that loving God is very important. As Jesus says, it is the first and greatest commandment. When a Pharisee who was a lawyer asked him, “Teacher, which is the great commandment in the law,” Jesus answered, “You shall love the Lord your God with all your heart, and with all your soul, and with all your mind. This is the great and first commandment” (Mt 22:36-38). We should love everyone, but first we should love God himself, who created the universe, and who loves each one of us so much that he sent his Son to die on the cross to redeem us.
What is more, God is himself love, infinite divine love, and he loved us first. St John writes in his first letter, “Beloved, let us love one another; for love is of God, and he who loves is born of God and knows God. He who does not love does not know God; for God is love… In this is love, not that we loved God but that he loved us and sent his Son to be the expiation for our sins” (1 Jn 4:7-10).
That said, we return to your question about what love for God is, and what it is not. First, it is not feeling that we love God, even though it is good to have those feelings. People in love for one another feel strongly for their beloved, they have the passion, the emotion of love, the form of love that we call eros. While it is good to have this feeling of love for God too, many people do not, including some of the saints. The classic example in modern times was Mother Teresa of Calcutta. For the last fifty years of her life she suffered from great spiritual dryness, in which she felt God distant, as if he weren’t there for her. Yet she continued to rise early and do all her prayers, including Eucharistic adoration, and to look after the sick and dying with tremendous generosity. During those years she didn’t feel the love for God, yet she showed it in her faithfulness to her spiritual exercises and her love for others. She is now, as we know, a great canonised saint.
Nor is love for God merely telling him that we love him. It is good to say, “Jesus, I love you”, but that in itself is not enough. Children can tell their parents that they love them, but if the children do not do what their parents ask them to do, their words are hollow. The parents might very well say, “If you love me, then show me that you love me by doing what I ask of you.” St Josemaría Escrivá once said to Jesus while he was giving Communion to some nuns, “I love you more than these.” He heard in reply, “Love is deeds, not sweet words.”
And, of course, love for God is not being without sin. St Augustine says, referring to the saints in heaven, “If we could bring here in living form all the saints of both sexes and question them on whether they were without sin, would they not exclaim unanimously, ‘If we say that we have no sin, we deceive ourselves and the truth is not in us’”? (1 Jn 1:8; De nat. et grat., 36)
Nor is love for God having many daily devotions. In this regard, St Francis de Sales cautions us in his classic Introduction to the Devout Life: “Those are spiritually greedy who never have enough of exercises of devotion, so keen are they, they say, to attain perfection, as if perfection consisted in the number of things we do and not in the perfection with which we do them… God has not made perfection to lie in the number of acts we do to please him, but in the way in which we do them: that way is to do the little we have to do according to our calling, that is, to do it in love, through love and for love.” In a word, loving God is doing the little things of each day with love.
St Alphonsus Liguori sums up succinctly what love for God is. He says that all of holiness consists in the love of God, and all the love of God consists in doing his will. Here we have in a few words the essence of what it means to love God. It is to do in every moment what God is asking of us, what our conscience is telling us, and to do it with love. This is within the reach of everyone. When we do it, as St Josemaria Escriva says, we turn the prose of everyday into heroic verse.