They were arrested on 13th May 2016 and charged with "acting against national security", alongside Youcef Nadarkhani, a pastor once sentenced to death for apostasy.
Miles Windsor from Middle East Concern, an organisation which defends the religious freedoms of Christians, told Premier Christian Radio: "Do be praying that these men would be acquitted, that they will be freed.
"Do also be praying that Iran would change tact in the way that it treats Christians and other religious minorities as well, other than Christians, so do be praying for those things."
There are fears Yasser Mossayebzadeh, Saheb Fadaie and Mohammad Reza Omidi could each be jailed for up to six years when they appear Rasht Revolutionary Court in Rasht (pictured above), northern Iran.
Explaining the background of the case, Miles Windsor added: "It is accepted that Christians drink wine in that context, however, they don't recognise Muslim converts to Christianity as Christians.
"They see them as Muslims drinking alcohol which is illegal there."
Nadarkhani and his wife, Tina, were arrested alongside Mossayebzadeh, Fadaie and Omidi, however, the couple were later released.
Middle East Concern says acting against national security is a charge often made against Christian converts who hold positions of leadership within the Christian community.
Rob Duncan from Middle East Concern added: "The Iranian regime is conducting a very active campaign against house churches at the moment and leaders of house churches are harassed and put under pressure."
The organisation reports more than 200 Christians have been detained by Iranian authorities since last year, with many currently in prison.
Click here to listen to Miles Windsor from Middle East Concern speaking with Premier's Hannah Tooley:
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