With this week marking three years since the Syrian war began, it is estimated that more than 140,000 Syrians have been killed. Open Doors has ranked Syria the third-worst country in the world for persecution, with Christians becoming increasingly vulnerable with violence against them escalating, particularly from extremist Islamist opposition groups.

In the land where St Paul was converted, churches are being damaged or destroyed and many Christians have been abducted, physically harmed and killed. The largest massacre of Christians occurred on 21 October 2013, when Islamist militias invaded the ancient Christian settlement of Sadad and killed 45 believers.

Just last month a jihadist group gave Christians in the northern city of Raqqa these three options: convert to Islam, submit to their demands or be killed. The Islamic State in Iraq and the Levant (ISIS) banned Raqqa's Christians from praying in public, renovating churches, displaying crosses or ringing church bells, and insisted they must also pay a regular levy in gold.

This Tuesday, 18 March, the independent commission of inquiry on Syria gave their latest update to the UN. Basing their evidence primarily on first-hand accounts, the investigators report that the violence is continuing from both the government and the many opposition groups. Since 20 January the Syrian government has stepped up their barrel-bombing of residential areas in Aleppo, causing huge civilian casualties and large-scale displacement. The commission has also found that the Syrian people are routinely denied medical help, electricity, food and water, leading to death-by-starvation.

More than 2.5 million people have fled Syria in the past three years, most to neighbouring countries including Lebanon and Turkey. Recent talks were held in Geneva in January to try and establish a transitional governing body. However these broke down after only two rounds, meaning a political solution is not likely soon.

Bishop Antoine Audo SJ has been the Chaldean Bishop of the city of Aleppo for 25 years. In a piece in The Telegraph the Bishop explains what Christians in Syria are facing: "It's hard to describe how chaotic, terrifying and psychologically difficult it is when you have no idea what will happen next, or where the next rocket will fall. Many Christians cope with the tension by being fatalistic: that whatever happens is God's will… Our faith is under mortal threat, in danger of being driven into extinction, the same pattern we have seen in neighbouring Iraq."

But amid the despair, Christians are working to bring emergency relief to tens of thousands of Syrians from all faiths. "It is dangerous work" Bishop Antoine explains: "Five months ago, two rockets hit (the Caritas) offices, and it was truly a miracle that no one was killed." The Bishop is also at risk of kidnapping, with other priests having been snatched.

Despite knowing the risks, Bishop Antoine says: "I cannot work unless I am in the streets to understand the situation and the suffering of the people. I am sustained by the daily acts of solidarity from my brothers and sisters around the world…with their prayers and donations. And as I walk through the dust and the rubble, I am not afraid."

Bishop Antoine and many others still have faith in God's protection and hope for the future of Syria. Open Doors reports that in the midst of civil war Syria is seeing growth in the number of Christian converts. One pastor told an Open Doors co-worker: '"We have prayed for a revival for years and now it's here, but we never expected that God would use a civil war."

Please remember to pray for Syria, individually and in your church:

• Pray for protection for the many believers who have chosen to stay in Syria to serve their communities
• Pray for workers and partners bring relief to thousands of displaced Christian families
• Pray for a peaceful end to the conflict that has torn this country apart.

Read more about Syria's civil war and access Tearfund's prayer resources.