Thirty-five per cent of respondents in a survey of approximately 2,000 people said they thought the trait was the top indicator.
But there was a considerable difference between the genders - with 42 per cent of women and 27 per cent of men favouring kindness above other qualities.
Love (14 per cent), goodness (eleven per cent) and faithfulness (six per cent) completed the top four characteristics.
The YouGov and Yahoo UK poll found joy, peace, patience, gentleness and self-control were less popular - each garnering five per cent or less of votes.
Speaking to Yahoo UK's 'Britain is a Nation Of' podcast, Church of England priest and reality television star Kate Bottley the idea of being a good Christians is a "crazy notion".
She said: "The basic point for me of Christianity is that I am an absolute failure and all Christians are. We mess it up continually, we get it wrong, we're hypocritical.
"We fudge it up on a second-by-second basis, we are not perfect people."
"It's not an awards ceremony, going to church, it's a hospital for the broken, that's what it's about.
"It's about going there and going, 'oh my word, I can't get this life right and I'm trying really hard.'"
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