'I woke up the next morning at some point in the bed in Colin Prichard's house. I was completely naked,' he said. 'I don't know what happened. I can only speculate and I expect you can speculate too.

'That really bothers me not knowing what really happened. It was terrifying.'

Roy Cotton was convicted of child sexual abuse in 1954 but was considered suitable for ordination in 1967 by then Archbishop of Canterbury, Michael Ramsey, as a 'man of considerable ability...free of any trouble for 12 years'.

The inquiry's lead counsel described Cotton as an 'alleged abuser hiding in plain sight'.

Johnson is now chair of the Minister And Clergy Sexual Abuse Survivors (MACSAS) support group and sits on the Church of England's independent safeguarding panel.

He said: 'It is utterly shocking that someone who had a child abuse conviction could not only be ordained as a priest but allowed to work completely unsupervised in a large parish in a big town with access to lots of young children and also to take children regularly on foreign tips completely unsupervised.'

On one such trip overseas Johnson said he was taken to the home of a Catholic priest in France who held a cache of 'Nazi propoganda' style pictures of young boys naked.

Cotton, who died in 2006, was accused by Johnson and others of abusing teenage boys, the inquiry heard, and also of providing his friend, Colin Pritchard, access to teenage boys to abuse. Pritchard, now known as Ifor Whittaker, was sentenced last month to 16 years' imprisonment of several counts of indecent assault and rape against a teenage boy between the ages of 10 and 15.

The inquiry was told on Monday that it would hear evidence of how senior clergy colluded with one another to enable children to be abused.

David Greenwood, a lawyer to a number of the victims, said: 'We will hear of bishops granting 'Permission to Officiate' certificates to convicted paedophiles and to those facing criminal allegations.

'There is a strong suspicion of an organised conspiracy between clergy and bishops in the Diocese of Chichester to enable children to be abused and it will be painful for all involved to hear.'

He added: 'We will hear in this Chichester inquiry of a culture in which burning paper files in the Cathedral yard was tolerated. Bishops ignoring past convictions and allegations was common place.

Johnson said the abuse had left him with 'classic symptoms' of post-traumatic stress disorder.

'It has had a huge impact on me. I think it affects my self-esteem, my self confidence. It affects how you form sexual relationships,' he told the inquiry.

'If someone touches me in a certain way, or a certain smell, and immediately you are an 11 or 12-year-old boy and terrified and frozen in that situation.

'You are never free,' he said. 'It is always there. It is like a stain on your soul.'