Titus, who suffered neglect until he was rescued by the RSPCA, was adopted by eight-year-old Lily Smith in May and now lives with her family in the village of Kilnwick, near Driffield, East Yorkshire.
The pony was part of a herd, all found thin, with overgrown hooves and suffering from lice after they were abandoned in 2016.
The village's All Saint's Church organised a special 'bring your pet to church day' yesterday (Sunday), in the hope of encouraging families, children and their pets to gather, meet new friends and receive blessings.
And the congregation was left stunned as when Lily saddled up with Titus and walked through the church doors for the event.
The youngster's mum, Jo Smith, said: "He stood really nicely for the service along with his pony pal Pepper and lots of local dogs and their owners.
"It was a lovely idea to encourage local families to come to church and make new friends, people absolutely loved seeing ponies there, it was a real talking point. Afterwards, we all stood in the church yard and enjoyed a cup of tea.”
Titus and his abandoned herd were rescued by RSPCA inspectors in March 2016, and cared for at RSPCA Felledge, a specialist equine centre in County Durham.
Ms Smith added: "Since we re-homed Titus in May this year, he has been so calm and taken everything in his stride, we were confident he’d be happy to attend the service.
"We rode across the fields from our farm to the church and Titus was happy to walk right in through the doors!"
The service was organised by All Saint’s church warden Tim Bristow, and led by the Rev Carole Aconley.
To find out more about re-homing a rescue horse or pony, visit www.rspca.org.uk/findapet/rehomeahorse