Theresa of Avila would sometimes become very bold in her prayer and say to God: Kiss me full on the mouth. This is her own twist to the opening line of the Song of Songs where the author prays: “Let him kiss me, with the kisses of his mouth!”

That is vary audacious prayer and, understood properly, a most radical one. For Theresa, this is a formula for the ultimate act of commitment and surrender. For her, you pray this prayer only when you are ready to give yourself completely to God with absolutely no reservations, hesitations, conditions or restrictions.

It is the ultimate prayer of single-mindedness, of purity of heart, of, in Kierkegaard’s famous dictum, willing the one thing. Kiss me full on the mouth! A mystic’s metaphor! When someone says this to God, it is a request to be taken completely, an offer of total surrender.

Steven Hawkings ends his A Brief History of Time by saying that, up to now, science and philosophy have found pieces of explanation for how and why things are as they are.

We have, he says, bits of information and valuable insights into reality, but lack a unified theory, a simple equation, he insists, should it ever be found, must be understandable by everyone, not just by a few scientists. The formula that ties all the bits and pieces together must be, in Hawkings’ view, utterly simple, something very primal.

Kiss me full on the mouth fits that description, not as the scientific equation that Hawkings is looking for to explain why it is that we and the universe exist, but as a formula tying together all the bits and pieces we know about prayer, love and surrender.

Here, just as in science, we have a lot of unrelated insights but generally lack a unifying formula. The mystics proposed such a formula and it is utterly simple and primal—Kiss me full on the mouth! To say that in prayer is to bind all bits and pieces of our “prayer and longing together and give them a single meaning and a single thrust.

But this isn’t a prayer that can be uttered easily. Nor, indeed, is it something that can be easily in truth said to another human being.

There is an innocent romanticism inside of us which lets us naively, but falsely, believe that true love and surrender are easy. This, along with other blind spots which are less innocent and inculpable, generally make us naive to the fact that there are many pre-conditions necessary for this prayer to be said and truly meant. What are those pre-conditions?

Inside of each of us there is major book which, should it ever be written, could be given the title: Kiss me full on the mouth. That phrase can serve as the hermeneutical key to help understand the constant struggle between resistance and surrender that rages deep inside each of us.

For we are born with two great drives, both of which try to claim us. On the one hand, we are driven by the longing to be free, independent, to set ourselves apart. On the other hand, we are equally as driven by the urge to merge, by the desire to lose ourselves, to give ourselves over to the great embrace, to return to the kind of primal intimacy that we lost at birth.

Our lives are simply chronicles of that primal struggle within us between resistance and surrender. The yearning for intimacy and surrender competes with the yearning for independence and control.

Thus, in both our love relationships and in our prayer, we vacillate back and forth: We give ourselves over and we take ourselves back; we want intimacy, even as we are fighting it; we strive for unconditionality in love even as we set all kinds of conditions; and we say, “kiss me full on the mouth,” even as we are turning our heads (and our lives) to avoid the full brunt of such an encounter.

Not until we reach the highest levels of maturity, altruism, selflessness and sanctity can we ever ask God or anyone else to kiss us full on the mouth and really mean it. Hence, love and prayer are, in the end, a struggle to say that prayer.

Jacques Maritain once commented that only three kinds of people think that love is easy: Manipula­tors, who have everything confused with their own selfishness; saints, who through years of practice have made virtue easy; and naive dreamers, who don’t have a clue what they are talking about!

Each of us is a manipulator, saint and naive dreamer, all at the same time. We struggle with love and prayer, with resistance and surrender. The mystic’s prayer: Kiss me full on the mouth, is the clue as to how those struggles must eventually be resolved.