An immigration tribunal judge, Louis Kopieczek, said the authenticity of the asylum seeker's claim was irrelevant given how the hundreds of Bible verses and other religious quotes posted on his social media page could make him a target for Iranian authorities.
He said: "In all the circumstances, I am satisfied that the appellant has established that there is a real risk that on his return he would be questioned about the details of his asylum claim and that questioning would reveal that he has posted on Twitter... [and] interrogation would involve a real risk of ill-treatment amounting to a breach of [his human rights]."
Known only as AM, the 38-year-old successfully applied for a UK residence card after failing to secure asylum the day he arrived in the UK in January 2006.
He was sentenced to five years in prison in 2013 for the rape of a 17-year-old girl and, following his release, the then-Home Secretary authorised his deportation. Theresa May claimed the main remained a serious threat to the public.
Following a subsequent legal battle, the judge ruled that deporting the individual could amount to a breach of his human rights.
Persecution against believers in Iran has been documented by organisations such as Open Doors.
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