The video of a black man being pushed by Chelsea fans as he tried to board a train on the Paris Métro has rightly caused widespread outrage.

The fans, who were likely in Paris for Chelsea's match against Paris Saint-Germain on Tuesday evening, repeatedly pushed the man off the train carriage, chanting "We're racist, we're racist, and that's the way we like it."

The footage was published by the Guardian yesterday and strongly condemned by Chelsea, who said: "Such behaviour is abhorrent and has no place in football or society," adding that they would support any criminal action taken against those involved.

Many have commented that the culture around football matches has dramatically improved in the past few decades, and there has certainly been significant effort to purge football of racist chanting and abuse.

The 'Let's Kick Racism Out of Football' campaign was set up in 1993 in response to calls from clubs and players to counter racist attitudes in the game, and has since broadened its scope as the charity Kick It Out, to work against discrimination. But the chairman of Kick It Out, Lord Ouseley has described racism as "a Chelsea problem, a football problem and a national problem".

We like to think that society is getting better and that we're learning from past mistakes. Although we know we're not perfect, people don't generally think it's ok to use the 'N' word, and the outcry over the video demonstrates that society doesn't tolerate racial abuse when it is exposed. But does this change the way we think? A report from the British Social Attitudes survey last year showed that the number of people who admit to holding racist views has increased in the last decade. This could be partly explained by greater self-awareness, or it could be because human nature is stubborn, flawed and sinful.

It is true that this behaviour shouldn't have a place in our society, but it does. And it's not just the overt examples of prejudice – be it racism, anti-Semitism or Islamophobia – but more subliminal prejudices that we all have, and which will generally go unnoticed, often even by ourselves.

The scary thought is that it doesn't take much to reveal the unpleasant views lurking underneath – whether through the crowd mentality where prejudicial views go unchallenged or after too many pints. There are numerous online tests that promise to reveal your personal bias, and maybe there's some truth in them, but it's also worth remembering that we need the Holy Spirit to reveal the sin in our hearts and lead us to repentance.

Equality is meant to be one of the highly prized values of our society, and still we have a problem. Imagine the blind spots to the issues that aren't so high on our cultural agenda.