Police are asking for Mercury readers' help in tracking down three men who tried to attack a standing safe in Priory Church, Deeping St James.
Money collected in this safe, ranging from donations to magazine payments, goes towards the upkeep and other running costs of the building.
The CCTV pictures show the men lurking in the church on the afternoons of January 24 and 25.
The vicar, the Rev Mark Warrick, said it would be impossible to know how much money was in the safe and that the thieves put something covered in adhesive through the safe slot to get at the money.
He was in church on the first occasion but did not see the men and was prompted to check the CCTV tapes after hearing them.
On the second day he walked into the church while the thieves were there but did not catch them in the act and they left soon after.
The Rev Warrick, of Church Street, Deeping St James, said: "Like another victim of burglary, you don't like the idea of money beng given for one purpose to be stolen for another.
"Theft is theft, it is always wrong and aways abhorrent."
Community beat manager PC David Bannister, who is based at Stamford police station, is appealing for information and is asking people to contact officers if they saw any suspicious activity near the church.
He said: "It is a despicable that certain members of our society have no respect for the church by pillaging it."
Anyone who recognises the men or who has any information is asked to call the police on 01780 752222.