As persecution of Christians continues to rise, churches everywhere will be gathering for the International Day of Prayer (IDOP) on November 16.
"Increasing numbers of Christians face violence, imprisonment and death as global instability and uncertainty increase," said Paul Robinson, chief executive of persecution charity Release International, which is supporting the day.
"But we know that prayers, coupled with actions, create change."
The charity says that persecution under Islam is often highlighted in the media, but Christians are also facing troubling circumstances under Communism, Authoritarianism, Hinduism and Buddhism.
For example, at least 30,000 Christians are currently being held in concentration camps in North Korea, while 1,000 are imprisoned without trial in Eritra. Increasing attacks are also being reported in India, and there has been a recent crackdown on churches in Iran.
Last week, Prince Charles passionately defended religious freedom during an address at the House of Lords.
He branded the ongoing violence in the Middle East "horrendous and heart-breaking" and called for a renewed commitment to interfaith dialogue.
"It is an indescribable tragedy that Christianity is now under such threat in the Middle East; an area where Christians have lived for 2,000 years, and across which Islam spread in 700AD, with people of different faiths living together peaceably for centuries," he said.
"Article 18 of the Universal Declaration of Human Rights is clear in stating that this right includes the freedom to change one's religion or belief. Yet even in the West this right is often challenged...My heart goes out to all those around the world, but especially at this time in the East... who are so brutally persecuted solely for the faith they profess. I pray too that all people in communities will engage in building respect and tolerance. For without these the very freedom on which society is built is threatened with destruction."
The Prince also a verse from Romans 5, and urged Christians to not give up in the face of persecution.
"It is important that on a personal level, we do not lose hope," he said. "'Suffering produces endurance, endurance produces character, character produces hope'. And hope does not disappoint us."
"For IDOP this year we focus especially on believers who have been imprisoned because of their Christian faith, and their families, who suffer separation from their loved ones. These are our brothers and sisters on the frontlines of faith, who have suffered great loss – and who need our support," Robinson said of November 16.
"IDOP is a time set apart for Christians around the world to remember our brothers and sisters worldwide who suffer persecution, simply because they confess Jesus Christ as Lord. Please do take part in this year's International Day of Prayer for the Persecuted Church, and stand together as one."
Release has produced free resources to help churches plan their times of prayer, find out more here.