The letter turning him down, stated the Bible is "filled with imagery of revenge, destruction, death and violence" and therefore inconsistent with the Iranian's claim.
Many church leaders criticised the decision while Home Secretary Sajid Javid said it was "totally unacceptable".
According to the Church Times the training was introduced after the All Party Parliamentary Group for International Freedom of Religion or Belief claimed Home Office staff were making poor decisions.
Speaking to the newspaper, Revd Mark Miller from Stockton who attended the first training session said: "Home Office case-workers have a really difficult job. But there have been a number of bad decisions over the years, highlighted as far back as 2004 by an Evangelical Alliance report, All Together for Asylum Justice.
"I have been involved in training to share some of my experiences of working with Christian conversion, and how to go about assessing whether someone is genuine. In the session, I asked staff what they thought was basic knowledge, but most of what they suggested back to me wasn't basic knowledge, it was 'Name the Ten Commandments', rather than the significance of a faith in Jesus."
In a statement responding to the training, the Home Office said: "The UK has a proud history of granting asylum to those who need our protection. We are committed to improving the quality and accuracy of decision-making to ensure we get decisions right the first time.
"The Home Office is working closely with members of the APPG for International Freedom of Religion or Belief, as well as representatives from a range of faith groups, to provide specialist mandatory training. The aim of this is to ensure decision-makers appropriately consider all the available evidence where religion or belief is raised in an asylum claim."
Speaking after the incident with the Christian convert earlier this year, Sajid Javid said he's ordered an urgent investigation and not ruled out any further action.
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