Mother Teresa begged archbishop to pray for her 'to see God again'

But letters revealed in a new biography show that she worked "in darkness" - without God.

And her "darkness" lasted for nearly 50 years.

Come Be My Light is edited by the Rev Brian Kolodiejchuk. The book draws on correspondence over a period of 66 years - letters she wanted to be destroyed after her death.

"I want the work to remain only His," she explained.

She feared that if they were revealed "people will think more of me - less of Jesus".

Mother Teresa, who was awarded the Nobel Peace Prize in 1979, set up the Missionaries of Charity in 1948.

She said Christ had "spoken to her" and called her to abandon her teaching work with the Loreto Sisters to work in the Calcutta slums with "the poorest of the poor".

She reported that Jesus had said to her: "Come be My light."

But by 1953 she was writing to the Archbishop Ferdinand Perier - whom she had petitioned to set up the Missionaries of Charity - to ask him to "pray for me".

"Please pray specially for me ... that Our Lord may show Himself - for there is such terrible darkness within me, as if everything was dead.

"It has been like this more or less from the time I started 'the work'."

Another letter to the Archbishop in 1955 said: "The more I want him - the less I am wanted.

"Pray for me please that I keep smiling at Him in spite of everything."

Mr Kolodiejchuk, who is a senior member of the Missionaries of Charity and Mother Teresa's chief advocate for her sainthood, says there was only one respite in her "darkness" for five weeks in 1959.

He collected the letters together as supporting materials to petition the Church. They include the confession that "I no longer pray" and a reference to Jesus as "the Absent One".

His research also records how Mother Teresa counselled Malcolm Muggeridge about his doubts.

The writer and filmmaker visited the Missionaries of Charity in 1968 with a film crew and his film, Something Beautiful For God was released the following year, making Mother Teresa an international sensation.

She wrote to him in 1970: "Your longing for God is so deep and yet He keeps Himself away from you."

Mr Kolodiejchuk told Time magazine that her emptiness makes her work all the more remarkable, says Kolodiejchuk.

And he is inspired by her letters. Despite her doubts there is plenty to underline her faith. In 1962 she wrote: "If I ever become a Saint - I will surely be one of 'darkness'. I will continually be absent from Heaven."