A recent book on Mother Teresa, "Mother Teresa: Come Be My Light," makes public a huge volume of her intimate correspondence and in it we see what looks like a very intense, 50-year, struggle with faith and belief.

Again and again, she describes her religious experience as "dry," "empty," "lonely," "torturous," "dark," "devoid of all feeling." During the last half-century of her life, it seems, she was unable to feel or imagine God's existence.

Many people have been confused and upset by this. How can this be? How can this woman, a paradigm of faith, have experienced such doubts?

And so some are making that judgment that her faith wasn't real. Their view is that she lived the life of a saint, but died the death of an atheist. For doctrinaire atheists, her confession of doubt is manna from the abyss.

Christopher Hitchens, for example, writes: "She was no more exempt from the realization that religion is a human fabrication than any other person, and that her attempted cure was more and more professions of faith could only have deepened the pit that she dug for herself."

What's to be said about all of this? Was Mother Teresa an atheist?

Hardly! In a deeper understanding of faith, her doubts and feelings of abandonment are not only explicable, they're predictable:

What Mother Teresa underwent is called "a dark night of the soul." This is what Jesus suffered on the cross when he cried out, "My God, my God, why have you forsaken me?" When he uttered those words, he meant them. At that moment, he felt exactly what Mother Teresa felt so acutely for more than 50 years, namely, the sense that God is absent, that God is dead, that there isn't any God.

But this isn't the absence of faith or the absence of God. It is, rather, a deeper presence of God, a presence which, precisely because it goes beyond feeling and imagination, can only be felt as an emptiness, nothingness, absence, non-existence.

How can this make sense? How can faith feel like doubt? How can God's deeper presence feel like God's non-existence? And, perhaps more importantly, why? Why would faith work like this?

The literature around the "dark night of the soul" makes this point: Sometimes when we are unable to induce any kind of feeling that God exists, when we are unable to imagine God's existence, the reason is because God is now coming into our lives in such a way that we cannot manipulate the experience through ego, narcissism, self-advantage, self-glorification and self-mirroring.

This purifies our experience of God because only when all of our own lights are off can we grasp divine light in its purity. Only when we are completely empty of ourselves inside an experience, when our heads and hearts are pumping dry, can God touch us in a way that makes it impossible for us to inject ourselves into the experience, so that we are worshiping God, not ourselves.

And this is painful. It is experienced precisely as darkness, emptiness, doubt, abandonment. But this is, in fact, "the test" that we pray God to spare us from whenever we pray Matthew's version of the Lord's Prayer: "Do not put us to the test."

Moreover this experience is usually given to those who have the maturity to handle it, spiritual athletes, those who pray for and truly want a searing "purity of heart," people like Mother Teresa. They ask Jesus to experience and feel everything as he did. He just answers their prayers!

Henri Nouwen, in the book "In Memorium," shares a similar thing about his mother: She was, he states, the most faith-filled and generous woman he had ever met. So when he stood at her bedside as she was dying he had every right to expect that her death would be a serene witness to a life of deep faith. But what happened, on the surface at least, seemed the exact reverse. She struggled, was seized by doubts, cried out and died inside a certain darkness.

Only later, after prayer and reflection, did this make sense. His mother had prayed her whole life to die like Jesus --- and so she did! A common soldier dies without fear; Jesus died afraid.

In a remarkable book, "The Crucified God," Jurgens Moltmann writes: "Our faith begins at the point where atheists suppose that it must end. Our faith begins with the bleakness and power which is the night of the cross, abandonment, temptation and doubt about everything that exists! Our faith must be born where it is abandoned by all tangible reality; it must be born of nothingness, it must taste this nothingness and be given it to taste in a way no philosophy of nihilism can imagine."

Mother Teresa understood all of this. That is why her seeming doubt did not lead her away from God and her vocation but instead riveted her to it with a depth and purity that, more than anything else, tells us precisely what faith really is.

Oblate of Mary Immaculate Father Ronald Rolheiser is a specialist in the field of spirituality and systematic theology. His website is www.ronrolheiser.com.