Services at St Peter’s Church, less than half-a-mile from the centre of Birstall, West Yorkshire, where Mrs Cox was killed on Thursday, highlighted her tireless work for those at “the bottom of the world’s heaps”.
The Rev Paul Knight told the congregation: “Her humanity was powerful and compelling and we would do well to recognise her as an amazing example - a 21st century Good Samaritan.”
He said she was “someone with whom Jesus would have been so pleased”.
Mr Knight said: “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.”
Mr Knight also remembered the bravery of pensioner Bernard Kenny, 77, who remains in hospital after he was injured as he came to Mrs Cox’s aid outside Birstall library.
The vicar read the story of the Good Samaritan from the Bible, saying it was a fitting message.
He said: “There is much wickedness in our world. But thank God there is so much goodness - goodness that does not recognise colour, not nationality.”
Parishioner Leif Wickes led prayers for Mrs Cox’s family during the Sunday service.
Mr Wickes said: “Pray for Jo’s and Brendan’s children - still too young to understand the horror of what happened but old enough to suffer from the loss of their mother.
“As they grow up and hear about Jo’s life and achievements, may they be inspired to follow her example and serve the world’s underprivileged in their turn.”
He prayed for Mr Kelly who, “despite his 77 years intervened in the attack to try and save Jo’s life and was stabbed and badly injured.”
He said: “We give thanks for his courage and his example and pray for his speedy recovery.”
And Mr Wickes prayed for the causes Mrs Cox supported, including children fleeing from war zones “seeking safety among us”, the people of Syria, children locally “left behind in comparison with children in London” and people living with autism.
He said: “Jo’s compassion for all at the bottom of the world’s heaps - help us to look afresh at the world through her eyes and to play our part in continuing the work that she undertook.”