Mother Teresa, who is one step short of being made a Catholic saint, suffered crises of faith for most of her life and even doubted God's existence, according to a set of newly published letters.
"Jesus has a very special love for you. As for me, the silence and the emptiness is so great that I look and do not see, listen and do not hear," the missionary wrote to one confidant, Reverend Michael Van Der Peet, in 1979.
The letters, some of which she wanted destroyed, appear in Mother Teresa: Come Be My Light, due to be published this week, 10 years after her death. Extracts of the book appear in the latest edition of Time magazine.
In more than 40 letters spanning some 66 years, the ethnic Albanian nun who devoted her life to working with the poor in the slums of Kolkata in India, writes of experiencing personal "darkness," "loneliness" and "torture."
"Where is my Faith -- even deep down right in there is nothing, but emptiness and darkness -- My God -- how painful is this unknown pain -- I have no Faith," she wrote in an undated letter addressed to Jesus. "If there be God -- please forgive me -- When I try to raise my thoughts to Heaven -- there is such convicting emptiness."
"I call, I cling, I want -- and there is no One to answer -- no One on Whom I can cling -- no, No One. -- Alone," she wrote.
In her early life, Mother Teresa, also known as "The Saint of the Gutters," had visions. In one, she talked to a crucified Jesus on the cross.
But the letters reveal that apart from a brief respite in 1959, she spent most of the last 50 years of her life doubting God's presence -- much at odds with her public face.
"The smile," she wrote in one letter, is "a mask."
In another letter, written in 1959, she wrote: "If there be no God -- there can be no soul -- if there is no Soul then Jesus -- You also are not true."
The book's compiler and editor, Reverend Brian Kolodiejchuk, is a member of Mother Teresa's Missionaries of Charity and petitioned for her sainthood.
"I've never read a saint's life where the saint has such an intense spiritual darkness. No one knew she was that tormented," Kolodiejchuk told Time.
Cardinal Angelo Scola, the patriarch of Venice, said on Saturday that the letters showed Teresa was "one of us, that she did all her work as we do, no more no less."
Even in the depths of doubt, Mother Teresa "always had recourse to the most elementary form of the exercise of one's will, that of asking Jesus each day to reveal his face," said Scola, who had already written about the letters in the Vatican publication Osservatore Romano, quoted by the ANSA news agency.
Mother Teresa was beatified just six years after her death, when the late pope John Paul II set her on a fast track to sainthood.
It was something the nun seemed to have predicted as early as 1962, when she wrote in one letter: "If I ever become a Saint -- I will surely be one of `darkness.' I will continually be absent from Heaven."