The porcelain figure was swiped by thieves earlier this week.
"Heartbroken" SA ministers have launched a twitter campaign with the hashtag #FindJesus in the hope that the "centre piece to Christmas" will reappear in time for the "big day."
Can you help find Jesus this Christmas? We're sad to report that a Baby Jesus figurine was stolen from a nativity set in our @shops_sa in Peterborough which helps vulnerable people. This is the latest item to go missing in a series of break-ins:https://t.co/vZ7Tg4fEvR#FindJesuspic.twitter.com/T4CGIEonQy— The Salvation Army (@salvationarmyuk) December 6, 2019
The Long Causeway shop has fallen victim to a number of "unseasonal" criminal attacks since its opening in April 2019.
In a previous incident vandals caused some £1,000 of damage after breaking into the store and smashing the cashier till.
The thief made away with just £1 found in the charity's collection tin.
It comes as the church and charity prepares for its busiest season supporting the poor and vulnerable over the Christmas period.
Peterborough Salvation Army minister Major Gary Chaundy said: "It's heart breaking that someone would steal the centre piece to Christmas especially when our faith in Jesus is the reason we feel called to serve our community through this shop.
"All we've been left with is a virtually worthless nativity - no-one wants to buy a set without the most important person in it.
"We just hope that it's someone who feels strongly that Jesus shouldn't be in the set before the big day itself and he's going to reappear in time for Christmas."
Profits from the store support a number of local community initiatives including a free debt advice service, care for the elderly, a food bank, and a winter night shelter for the homeless.
Store manager Philippa Millard added: "Thankfully, the hurt we feel from the break-in and theft cannot overcome our commitment to help those who are struggling this Christmas. We will continue to open our doors and spread the good news that is found in that nativity scene."
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