Data from Stewardship - an organisation supporting over 250,000 people in missionary projects - shows most full-time volunteers in Christian ministry forgo basic needs and fail to meet financial demands throughout the year.
Chief generosity officer Daniel Jones told Premier there's a broad range of reasons workers can struggle to make ends meet: "Often it's with incidental expenses. Often it will be getting by on just enough, relying on sometimes some direct support from close family or friends.
"But it's when some of those bigger expenses hit that problems occur - the car breaks down, there isn't anything in the savings pot to cover a rent increase, etc.
"For people working overseas often it might be cases of illness where there isn't the NHS that they can fall back on and therefore having to pay for additional medical costs."
The organisation have launched a new campaign to provide volunteers with additional support over the Christmas period.
Jones says the essential needs of individual workers can vary depending on a number of factors.
"We'll look at which part of the world they're working in, the nature of the work that they're doing, the particular expenses that might be involved, whether a lot of travel might be required, the number of children they need to support and come up with a very specific calculation for each Christian worker."
There can be stigma in asking for financial support in the missionary field, says Jones, as some link it to a lack of faith in God's provision.
He argues that although reliance on God is always essential, this doesn't mean we can't seek help: "I see evidence in the Bible of times where God's people have been shown and encouraged by the Lord to fundraise and to go to others within the community of believers to say, 'Look, I'm doing this particular gospel work, please, will you will you support me?'"
The organisation have launched a new campaign in a bid to give every Stewardship full-time Christian Worker additional support of £100 over the Christmas period.
At the time of writing, the campaign has raised £41,805, 17 per cent of its £250,000 target.
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