Tony Blair has spoken to the BBC about his first spiritual experience, which occurred when he was a child.
The ex-prime minister said that praying for his atheist father when he became seriously ill had "a tremendous impact" on him.
Elsewhere in the interview with Joan Bakewell, Mr Blair defended the decision to invade Iraq, and insisted that faith schools are not divisive.
He also said that he reads the Koran nearly every day.
Mr Blair also spoke about the role of faith schools in the state sector.
During his time as prime minister, the academy schools programme was launched.
He believes that expanding faith school provision helped to foster inter-faith relations, adding that a question of equality was involved.
"You can't say to Christians and to Jews that you can have a faith school but Muslims can't".
"I think they can help give a sense of values, they can ground a child, they can instil a certain amount of discipline, in the right way, in a child's mind, provided that they approach religion in a non-sectarian way."
He also spoke about the motivations of insurgents in Iraq and Afghanistan, and rejected arguments that British foreign policy has radicalised Muslims.
"I think actually these acts of terrorism are utterly evil, yes. And when you think of the numbers of wholly innocent people that have died... I say the responsibility lies with the people doing the terrorism, 'cos there's no reason for them to do the terrorism.