The fear of kidnappings, a dwindling number of worshippers, and shrinking church finances mar the first Christmas in Muslim-majority Sudan since the Christian South separated, church sources say.
"We are going to have a Christmas like parents without children," said one source.
Like others, he asked to remain anonymous because of the sensitivity of the issue -- in particular the alleged abduction of ethnic southern youth to fight in the country's southern border region or with rebels in South Sudan.
"The young people are worried about being rounded up to serve in militia on the border," another church source said. "They take them to the camp, train them for a few weeks and then they send them."
Sudanese forces in the country's South Kordofan state have since June been fighting former allies of the rebels who fought for the independence of South Sudan. The South gained independence from the mainly Arab Muslim north in July after a two-decade civil war, and an overwhelming vote to break away.
The fighting spilled into nearby Blue Nile state as Khartoum moved to assert its authority within its new boundaries.
Philip Aguer, South Sudan's military spokesman, made essentially the same allegations as the church sources in Khartoum.
He said ethnic South Sudanese in Khartoum were among those particularly vulnerable to forced recruitment.
"They are sending them to the training camps of Sudan Armed Forces" and then dispatching them to areas including South Kordofan and Blue Nile, or to the forces of George Athor fighting in South Sudan's Jonglei state, Aguer said.
The Juba government announced on Tuesday that Athor had been killed in a clash with its forces.
Sudan's police spokesman could not be reached for comment on the allegations of forced conscription.
"Some youth are becoming a target" in the Sudanese capital, a third church source said, adding the insecurity could affect attendance at midnight services planned for Christmas Eve on Saturday, although churches are asking the authorities to provide protection.
A clergyman and two others were recently held for three days in a suburban home after plainclothes men jumped from a pickup truck and surrounded them after they had left a prayer meeting, sources alleged.
They said the three were released after paying thousands of Sudanese pounds (more than $1,000).
"There is a lot of insecurity and we are afraid," one church source said.
Churches are already struggling to deal with increasingly empty pews after, according to the United Nations, almost 350,000 ethnic South Sudanese headed to the South since October last year.
"Every Sunday we set maybe 10 or 15 minutes' time to pray for those who are going," said Canon Sylvester Thomas, dean of All Saints Episcopal Cathedral in Khartoum.
"Last Sunday we had about six of them who are leaving".
Even the cemetery is emptying, as some returnees dig up the bones of their relatives to take with them, Thomas said at his church, while the evening Muslim call to prayer sounded from a neighbourhood mosque.
Each traveller receives a certificate of appreciation and thanks.
"As you go to the New Nation, South Sudan, go with our Love, prayers and God's blessing," it says.
The Anglican cathedral, once overflowing, has cut back its services and the Sunday morning English mass may now only draw four or five people, Sylvester says. The Arabic mass attracts a few dozen faithful.
Offerings and tithes which supported children's education, medical treatment and women's training, are down 70 to 90 percent, he said.
"We are even having a problem now of paying the staff working with me," said Sylvester, whose church marks its centenary next month.
Uptown at St Matthew's Catholic Cathedral beside the Blue Nile River, Father John Dingi has similar challenges, with attendance down 25 percent or more after the departure of many English-speaking civil servants who left for the South.
Although the cathedral seemed almost full with about 300 parishioners for the Arabic service last Sunday, Dingi noted that most of them were men -- civil servants laid off after the South's separation.
When they get their settlement from the government, they too will head south, he said.
The future is uncertain, but Christmas remains a time to celebrate their faith.
Parishioners packed the yard of All Saints last weekend for a Christmas concert beneath strands of miniature white lights. Some raised their arms in praise, and gently swayed to joyous African music.
In a newly-divided country, priests said their Christmas message is one of peaceful coexistence, and reconciliation
"When we are reconciled there is justice.. and this one leads to peace," said Dingi.