Revd Paul Knight told a congregation at St Peter's Church in the West Yorkshire community that the 41-year-old MP was "someone with whom Jesus would have been so pleased".
He was speaking after Ms Cox was killed in the street on Thursday outside her constituency advice surgery.
Revd Paul Knight said: "Her humanity was powerful and compelling and we would do well to recognise her as an amazing example - a 21st century Good Samaritan."
He went on: "Jo was someone who went out of her way to help others.
"I regret to say I didn't know what she was like as a girl but she grew into a fervent advocate for the poor and oppressed.
"And though she must have been angry at times about what she saw here and around the world - those places she visited and worked - she seemed to me, at least, to be one who could fight with a passion and a disarming smile."
Jo's husband Brendan tweeted: "Jo loved camping. Last night the kids & I camped in her memory& remembered the last time we were all woken by the dawn chorus #MoreInCommon."
Jo loved camping. Last night the kids & I camped in her memory& remembered the last time we were all woken by the dawn chorus #MoreInCommon
— Brendan Cox (@MrBrendanCox) June 19, 2016
During the service at St Peter's prayer were said for Mr Cox and the couple's two young children.
Revd Paul Knight also remembered the bravery of pensioner Bernard Kenny, 77, who remains in hospital after he was injured coming to Mrs Cox's aid outside Birstall library on Thursday.
After reading the story of the Good Samaritan from the Bible, the vicar said: "There is much wickedness in our world. But thank God there is so much goodness - goodness that does not recognise colour, not nationality."