Officials in Tehran charged four men with “acting against national security” and drinking alcohol after they took part in communion.
Pastor Yousef Nadarkhani, Mohammadreza Omidi, Yasser Mossayebzadeh and Saheb Fadaie have been sentenced to ten years in prison each.
In a further blow Nadarkhani and Omidi were given additional sentences of two years in exile in southern Iran.
Drinking alcohol in Iran is forbidden under the country’s strict Sharia Islamic law, but despite the ban, enjoying a sly tipple at home is believed to be widespread amongst its 80 million strong population.
Holy Communion wine, also known as sacramental wine, is used by billions of Christians worldwide in celebration of the Eucharist.
It is often watered down and is used during Holy Communion alongside small bread wafers, known as Sacramental Bread.
The authorities accused the men of “propagating house churches” and “promoting Zionist Christianity”.
Charity Christian Solidarity Worldwide (CSW) condemned the sentences and said the Christian community in Iran has been criminalised.
CSW’s chief executive Mervyn Thomas said: “We are deeply disappointed by these excessive sentences, which are based on spurious charges and are clearly part of an intensified campaign of judicial harassment aimed at intimidating members of minority faiths.
“We reiterate that the national security charges levelled in all of these cases amount to the criminalisation of the Christian community for exercising the right to freedom of religion or belief, and that this is occurring despite the fact that the Iranian constitution recognises Christianity.”
Omidi, Mossayebzadeh and Fadaie were initially sentenced to a public flogging but have appealed against the punishment.
It is unclear when the court will rule on the sentence of 80 lashes each.
Offenders are normally sentenced to between 10 and 100 lashes across the back with a three-foot long whip.
Many people faint after eight strokes due to the severe pain.
The use of the corporal punishment has come under fire from humanitarian organisations who say the penalty amounts to torture.