I have known for a long time that the environment was in trouble; that climate change was a serious threat to our future, and that urgent action was needed. I'd made some changes to my way of life; we were with a green electricity provider, I avoided plastics where possible, and I signed online petitions when they came my way. And as a Christian and a parish priest, I knew that creation mattered, and that God cared how we lived in and with the world he entrusted to us.

But, if I'm honest, it wasn't high on my priority list. I didn't preach on it, our church wasn't much engaged in it and when we made decisions, other issues were more significant.

And then, in 2018, the Extinction Rebellion protests took over central London and the front pages. On Maundy Thursday that year, the day that Christians remember Jesus washing his disciples' feet, a group of Christians joined the protests. They went to wash the feet of the protesters and anyone caught up in the mass blockades.

I had been deeply struck by the commitment of people, young and old, from every part of the country and every background, who were willing to cause such disruption to our capital city and to their own lives, to tell the world that climate change is a disaster heading our way at express speed. And so, I went to join the foot washing group.

We went to Hyde Park Corner and, on a hot spring day, knelt down and washed the feet of the protesters camped on the pavements and in the park. It wasn't a big deal for them, but it was for me. Washing their dirty feet was a symbolic act of service to them and their cause, and a deeply personal commitment to care for God's beautiful, broken creation.

Fast forward three years and I'm now the Bishop of St Germans, overseeing the Diocese of Truro and its 200 parishes. And I'm proud to say that climate justice isn't just on our agenda, it's at the very top.

The terrible destruction that our – my – way of life is causing the world is already causing horrific suffering to the poorest and most vulnerable people around the world. And it's only just beginning.

I've got four teenage children, and I know that this matters to young people. A UN Development Programme (UNDP) poll in January found that two thirds of people think climate change is a 'global emergency', with 69 per cent of young people aged 14 to 18 showing the greatest concern. And a recent Tearfund UK poll discovered that nine out of 10 Christian teenagers were not only concerned about climate change but wanted to take action to do something about it.

I've had the immense privilege of working with some of these teenagers and in partnership with Tearfund and CreationFest, encouraging them to write an open letter to the G7 world leaders who are gathering in Cornwall in a few days' time.

It was important to me not just to bang my drum, but to find out what young people really thought, and to amplify their voice. We wanted to gather data, find out their opinions and then to support them to make a tangible and meaningful difference.

There was an urgency and an authenticity to what these young people wanted to say. There is a rawness to their call that the world needs to hear. Of course, we can encourage, but we need to step aside and let them do the talking.

I'm sorry to say that the Church hasn't led the way in this discussion. In fact, we've been behind the curve for many years. But that's changing. I want to join our young people in encouraging everyone in the Christian community to cherish and care for the creation that they're responsible for – whether it's their back garden, the community playground or their local countryside.

And in the church across Cornwall, we are committed to cutting carbon to net zero by 2030, to using our voices to speak prophetically and to moving towards a more balanced relationship with the earth and resources.

Our amazing young people have spoken. Their campaign is gaining momentum and they're not giving up. If I had the chance to speak to the Prime Ministers and Presidents who are about to gather for the G7, my message would be clear – listen to these young people; hear what they've got to say and do what they're calling you to do.

Hugh Nelson is the Bishop of St Germans in the Diocese of Truro. He is responsible for the creation care agenda for the Diocese and is absolutely committed to supporting, encouraging and challenging church communities across Cornwall to cherish creation, cut carbon and speak up.