Suchet, 71, - best known for his role as Hercule Poirot - said he began having doubts after conversations with people of different faiths for a ten-part Audible podcast called Question of Faith.
Speaking to The Times about why he is having doubts about his commitment to the Church of England, he said: "I'm not a great fan of organised religion. But that's really as a result of making these fantastic programmes."
Asked how his faith has changed, he added: "More spirituality - Christian spirituality because that's where I was moved towards, but very much away now from doctrine and dogma, which I find very polemical."
Suchet came to Christ after reading Romans 8 in a hotel. In an interview with Strand magazine he said: 'I'm a Christian by faith. I like to think it sees me through a great deal of my life.
"I very much believe in the principles of Christianity and the principles of most religions, actually-that one has to abandon oneself to a higher good."
He told The Times about his experience hearing from Kamal Khatib - a Muslim preacher based in Israel - for the documentary.
"I met Kamal Khatib, this hate preacher, really anti-West. I could see this man, this preacher, rousing his congregation who all would shout 'Allahu akbar'. They would all become incensed. It was like Henry V, 'Once more unto the breach, dear friends'."
However, he said he found himself looking past Khatib's 'manipulative' words when he spoke to him.
"He was a man with such conviction about Islam and the caliphate and what he took to be his vision of the Koran that I found myself leaning forward and going 'really?'
"I found myself empathising. I didn't have sympathy but my interest was growing and I wanted to know more."
He also spoke to Rev Canon Andrew White, who was known as the Vicar of Baghdad for his ministry at the last Anglican church in Iraq.
"As [Rev White] said, when religion goes bad, it goes very, very bad and only religion can solve it. A lot of the problem with fanatical behaviour is taking religious texts out of context and quoting them word for word.
"The majority of Muslims that I've ever met are the most wonderful, spiritual people."
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