A gay Christian Palestinian man born into a family of prominent Hamas supporters is appealing for help to save his life.

In a blog post in The Times of Israel, the Muslim-born man, rechristened John Calvin after his conversion, says that because he was born to a radical family, the government of Canada where he now lives wants to deport him.

His story is of almost indescribable horror, as he suffered terrible abuse from fellow Muslims before he turned to Christ.

A petition has been set up on change.org to help him and the human rights campaigner Peter Tatchell is among those lobbying to help him on Twitter #savejohncalvin.

In his post Calvin, 24, writes: "I need you to save my life... Don't worry, this isn't a scam. I'm not asking for money, or a spare kidney. But it isn't a joke either. There isn't a punchline. I really do need your help."

He says he cannot reveal his birth name but was born into one of the most pro-Hamas families in the West Bank. His grandfather was one of the founders of Hamas.

"From as early as I can remember, I was taught that Islam was the one true faith, that violence was the only answer, and that the Jews were our enemies. These were facts, as real and obvious as the fact that the sky is blue. These were 'facts' and deep down I wasn't sure if I believed them."

He says he knows that lots of people lose their faith and change their minds when and where they least expect it. "My moment arrived in an Israeli jail, after I was arrested for illegally crossing the border, escaping from yet another argument with my family and the violence of my father. I was looking for answers to questions when and where I least expected them."

It was in an Israeli jail that he finally questioned everything he had ever been taught. "Another man, a Palestinian man, hurt me in a way I could never have imagined, in a way that just isn't talked about in our society. If that was unexpected, that was nothing compared to what came next. The Israelis who worked in the prison – 'the Jews' – looked after me and took care of me, making sure the story never got out to those who would use it against me. The Palestinians I had been taught to die for had hurt and abandoned me while the Israelis I had been taught to kill acted with compassion and helped me heal."

Previously, he has said explicitly that he was raped.

Shortly after this began his journey of conversion, opening his eyes and heart to Christianity.

"When my parents found out, my father attacked me with a knife. I escaped, but when I later I met him, he beat me up and had me arrested. I'm not entirely sure how I survived being jailed with men who knew of my conversion but somehow I did. But I also knew that my time and luck were running out."

This was how he ended up in Canada, on a paid scholarship at a Christian college.

But due to his being born into a Hamas family, he faces deportation and almost certain death.

"Speaking to Israelis! That is a death penalty. Converting to Christianity! That is a death penalty. Being open about my sexuality! Again, that is certain death. If I am deported, sent back to where I was born and raised, it's only a matter of time before I am found dead."

He says he just wants to live in a place where he can be free to be Christian, gay, and Palestinian, and a hundred and one other things. "My name is John Calvin, and I want to live in a country where I'm free to forget about the circumstances of my childhood. My name is John Calvin and, most of all, I want to live. My name is John Calvin, and I need your help, desperately."

The petition on change.org calls for people to imagine if, because of your religion, political beliefs and sexuality, their own family would have them killed, to imagine if the only way to survive was to escape the society you were raised in.

"And now imagine you'd made a new life for yourself in a different country – only to be told you were about to be deported back to those who want you dead."