The Mass booklet included an image of Mageean's greatest achievement on the track, the moment she crossed the line at the 2024 European Championships.
In his homily, Father Martin Kelly, who knew Mageean from her childhood, spoke of her accomplishments, her love for her husband and the joy and pride she had brought to her hometown.
Kelly recalled visiting her in hospice shortly before her death, when she suggested they go for a walk.
Despite her illness, Mageean noticed he was struggling and offered to link arms with him.
"On the way down, she knew I was struggling and she said, 'Let me link you'," he told mourners.
"One of my happiest moments and memories is that of Ciara Mageean linking my arm as we walked back to her room."
The athlete represented Ireland at the 2016 and 2020 Olympics and won gold in the 1500m at the European Athletics Championships in Rome in 2024.
She also represented Northern Ireland at the Commonwealth Games, winning silver in Birmingham in 2022.