Do you desire God? I don’t mean simply love Him. I mean: Do you yearn and long for God?

We can agree, I take it, that loving God merely from a sense of duty is insufficient. Or can we so agree? By doing something from “duty” I mean doing it from a sense that you “have to,” that it is your “obligation,” that a law requires you to do it, and that you will be punished if you do not.

Not very long ago, that sort of approach to the Catholic religion was viewed as extremely admirable. We go to Church on Sunday because we have to. We do not eat meat on Friday, because a law forbids it, and we may be punished by God if we disobey. And so on. Upstanding Catholics were those who walked around, very serious and somber, brooding over their many obligations.

Notice that someone who approaches the faith in this way puts everything on a level. It is all a matter of “duty”: eating fish as much as going to Church. And, therefore, all of these things can equally be jettisoned, the moment that “duty,” as a motive for being a Christian, recedes into the background -- as it should. With this we may explain much of the breakdown of observance among Catholics after the Second Vatican Council.

Duty is cold; it implies that our heart is not really in a thing. There would be something wrong with a boy who gave his mother a hug because it was his duty. If a husband calls his wife from work because he “has to”-- although that may be a good start, and better than nothing -- this shows that he does not miss her enough.

Love means never having to say you “have to”: those are unnecessary words for lovers, who do what their beloved wants immediately, and because they want to, before any question of “have to” even arises.

So duty is not enough, as we knew already: we should love God with our whole heart, whole soul, whole strength, and whole mind.

But then the question arises: What sort of love should we show towards God? After all, there are many kinds of love. Brother loves brother in one way, as a friend. A child loves his father in another way, affectionately trusting him. Again, the love that a husband has for his wife is one sort of thing, and it is different from the love that a wife has for her husband.

We are quick to grant that “Jesus is your best friend.” Likewise, following the example of Christ, we pray the Our Father and say “Abba,” affectionately turning to God as our heavenly Father. As regards these truths, our fault is perhaps not that we fail to acknowledge them, but that we take them for granted. It should shock us, make us dizzy with wonder and astonishment, that God is our Father. If we truly appreciated the offer of friendship that Christ extends to us, we would place nothing above this.

But the love that a bride has for her bridegroom -- this, I think, we actually hold back from God. What sort of love is this? It is an eager love. It is passionate and self-effacing -- shameless, really. (Think of the Syrophoenician woman who, in effect, begged for crumbs from the table, so that her daughter might be healed.) Yes, it is love of yearning and desire. “Sicut cervus desiderat ad fontes ... .” “As a deer pants and faints for streams of flowing water, so my soul longs for you, my God.”

Does God want us to yearn for Him in this way? Is He actually hurt if we do not? This much, it seems, we can say: If He loves us in that way, and yet we do not love Him similarly in return, then He will be pained with unrequited love. And He surely does love us in that way: “I have come to set the earth on fire, and how I wish it were already blazing! There is a baptism with which I must be baptized, and how great is my anguish until it is accomplished!”

Why would Christ compare Himself to a bridegroom, if He didn’t want us to love Him as if we were His bride? What explains, otherwise, the language of the Song of Songs? “On my bed at night I sought him whom my heart loves--I sought him but I did not find him.” Haven’t St. John of the Cross and St. Teresa of Avila taught the Church about this sort of love for God? Didn’t John Paul the Great teach us always to yearn “to see the face of Christ”?--since it is only a lover who longs to gaze on someone’s face.

You might think: “This is some abstract height of mystical love, which I cannot achieve. It is beyond me.” Not so! As the saints have taught us, attaining this love is as simple as: Go to confession (especially if you must), and then receive what He called “my body” and “my blood.” Before you do so, pray: “I long to receive you. I desire earnestly to be united with you, and I give my entire self to you.”

Make the Eucharist the “center and source” of your life--and then you will requite the love of the Eternal Lover, who offered up His body and blood for you.

Michael Pakaluk is a professor of philosophy at Clark University. He lives in Cambridge, Mass., with his wife and children.