Rev Hassan Abduraheem Kodi Taour and Rev Kuwa Shamal Abazmam Kurri along with Abdulmonem Abdumawla Issa Abdumawla and Petr Jasek (a Czech national) are accused of crimes against the state. The harshest sentence for some of the crimes is the death penalty or life imprisonment.
Clockwise from top-left: Rev Hassan Abduraheem, Petr Jasek, Rev Kuwa Shamal, Abdumonem Abdumawla
According to Religious freedom group Middle East Concern, after several court hearings, including two this week, the prosecutor and the complainant have now finished their case and a judge will now give a verdict on whether the trial can continue on 2nd January.
The most recent hearing saw the four men being questioned by the judge.
Speaking with Premier, advocacy and development manager at Middle East Concern, Miles Windsor, said: "This is a critical juncture in the trial.
"The judge can now decide whether or not the evidence that has been presented is solid and reliable enough, and whether to proceed with the trial or whether to release the men."
Asked how the men are doing Miles Windsor said: "I think that they are on reasonably good form.
"Obviously, it's frustrating and painful to have to spend another Christian in prison in Sudan but my understanding is that they're doing OK."
Middle East Concern is calling on Christians to pray for the men.
It said: "[Pray] a. that the four imprisoned men will know the Lord's strength and comfort during their ordeal.
"b. that the witnesses will not be subjected to undue pressure and will be able to give their testimonies without any fear.
"c. for a fair judicial process, and that all who are detained will be released soon.
"d. that church leaders and other Christians will know the Lord's peace in the face of increasing pressure against churches in Sudan.
"e. that all officials involved will love mercy, act justly, learn about Jesus and choose to follow Him.
Click here to listen to Miles Windsor from Middle East Concern speak with Premier's Alex Williams: