ABOUT 500 chaplains have this week issued a warning to a Toowoomba father that they will not go without a fight.
Toowoomba's Ron Williams will next Tuesday start his High Court challenge over the legitimacy of Australia's chaplaincy program.
Mr Williams claims the program, two-thirds of which is funded by the federal government, breaches the Constitution.
Scripture Union Queensland CEO Tim Mander said if the challenge was successful, it would be devastating to the future of 2500 chaplains nationwide
"The natural consequence would be if that (challenge) was upheld, then all the funding would stop for 2500 chaplains across the country," Mr Mander said.
Scripture Union Queensland has received more than 30,000 statements of support which are expected to increase to 50,000 by the time the challenge starts.
Despite the support, Mr Mander would not predict the outcome of the challenge.
"I'm not a High Court judge," he said.
"All I know is that there's overwhelming support for this program in the community . . ."
The case will be heard in the High Court in Canberra from Tuesday to Thursday next week.