Jonathan Aitken was an MP in the Thanet area for 20 and held a Cabinet position under John Major.
In 1999 he was sent to prison for perjury and perverting the course of justice but whilst inside he read the Bible more, having attended an alpha course in the past, and became a Christian.
He later studied theology at Oxford and became an honorary president of Christian Solidarity Worldwide.
In an interview with The Sunday Times, he said he was looking forward to being ordained: "I am having a slight struggle tempering my enthusiasm with proper Christian humility."
Mr Aitken, 75, said that various clergymen asked him about his "past sins", about which he said: "I don't know if they went through the press cuttings".
He will be ordained by the Bishop of London, Sarah Mullally on 30th June and become a prison chaplain, helping inmates deal with loss, self-harm and suicide attempts.
Speaking of going into ministry later in life he said: "I feel I've got the energy for it and, above all, I've got the calling for it"
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