When Pete Greig walks into the room, people take notice. He has an intensity about him despite his relaxed demeanor and casual dress. Today we are meeting in a converted dance studio near the centre of Guildford which is the current home of the Emmaus Church community, founded by Greig and his wife Sammy. He's wearing a brown shirt and jeans, and his round plastic-rimmed glasses, leather satchel and salt-and-pepper beard give him a distinguished appearance. Couple that with a classic 1964 Morris Minor convertible and it gives the distinct impression that Greig was a hipster before hipsters existed. There's very little pretense about the man who's disarming smile puts everyone at ease, and it doesn't take long before jokes are being cracked and the whole room is laughing.

But it is contagious praying that Greig is best known for. He is the founder of the 24-7 prayer movement, which is now an international, interdenominational movement of prayer, mission and justice working in more than half the countries in the world. 24-7 is helping people in more than 12,700 locations to encounter God and engage with the needs of the world. The movement was birthed out of a vision Greig received from God on the same day as the September 11 terrorist attacks in 2001.

Unusually, Pete is not here to talk about prayer, however – instead, his focus is books. But how does he makes time to read when he has a frantic global travel schedule and is leading a church, writing books and speaking everywhere from Holy Trinity Brompton's Focus conference to the 24-7 global gathering in Switzerland?

Pete explains: "Reading isn't really about reading, it's about 'do we want to learn?' To learn from those who perhaps know more than us; who have done things that we'll never do. So if we are not making time to read books or listen to books, or read them on whatever platform, then we are missing out on growing in our own thinking and our own discipleship. If you're too busy to read a book then you probably are too busy. Because you're going to truncate your own spiritual development and if you're too busy for that then you're going to be a bonsai tree – you're going to be a mini version of the person you are created to be."

This turn of phrase captured my imagination. I must admit I like the intricate details of a Bonsai tree, and the incredible perseverance and skill it takes to grow them so perfectly. I once visited a Bonsai arboretum in Singapore and found their miniature beauty quite captivating. But Pete is using this comparison in the negative sense – we will only be a fraction of what God wants us to be if we don't read. The Bible talks often about big trees: the one that grows from a tiny mustard seed giving shelter to birds. Or the "oaks of righteousness" that are restored to joy from mourning in Zion. There is a sense of scale and security that these great trees bring to a landscape. I like the idea that investing in reading is making sure that we can become a thriving and flourishing tree, firmly rooted in the deep and rich things of God.

Pete goes on further: "It's important to learn from others. It's important to have time to reflect. It's important to engage with those who disagree with us and can stimulate our neural pathways. Reading is proven to be one of the most effective ways of doing that. So it's really important that we don't lose the art, the discipline, and the science of engaging with the written word. It's a key to our discipleship."

The idea that reading is reprogramming our synapses reminds me of a book by Nicholas Carr called The Shallows. He argues that our always-on instant-messaging culture, together with our our shortening attention spans from constant over-stimulation, are rewiring our minds to make it more difficult for us to read deeply. So Pete's idea that investment in reading is going to train our brains to fight back against this is a powerful one. But more than that, he sees it as a fundamental aspect of our discipleship – and therefore an important spiritual discipline.

I challenge Pete to identify the three books that have most impacted his life. It's a struggle for him to restrict himself to three and he sneaks in an extra one; you'll have to watch the video below to find out which one it is. But here are his thoughts on his top three:

1. One of my favourite books that I read as a teenager is Cry the Beloved Country by Alan Paton. It's a very old book – it came out in 1948.

But it's extraordinary because I think this is really the book that gave me a social conscience. Something came alive in me as I read the descriptions of South Africa... This was published a few months before apartheid was institutionalised, and you see where it came from; the massive unfairness and the divisions along racial lines. And of course this book is possibly even more prophetic now post-apartheid. There's this amazing line where the hero, who is a black South African, says this: "I have one great fear in my heart that one day when they (that's the whites) are turned to loving they will find that we are turned to hating."

So this is a book about social justice but also reconciliation. And I think it switched on the neural pathways for me and made me realise that as a human and a Christian I must care about the poor, about injustice and about the walls that we build to divide us.

2. One of the most important books for me as I was starting out in Christian leadership was by Richard Foster called Streams of Living Water.

It's not his best known book – his best known book is probably Celebration of Discipline. But I think it's seminal because he traces all the different types of church down the ages – the liberation stream, the charismatic stream, the evangelical stream, the liturgical stream. And he shows how each one of them has an essential message, an essential contribution, to the whole that is the body of Christ. And he traces the history; the historical characters. So, for example, the hero he uses of the charismatic tradition is not John Wimber – it's St Frances of Assissi. And so then what he does, and I think this is brilliant, is he says – "if this tradition, this stream, doesn't interface with the other streams this is where it goes wrong". For example evangelicalism becomes pharisaism, the liberation stream just becomes dead religion – social justice without any personal salvation and so on.

And so this is a brilliant summary of why as Christians we need to celebrate our differences, work together and enjoy the diversity of the church rather than feeling we've got to apologise for it. This was incredibly important in setting the DNA as 24-7 was beginning. We are working with everyone from the Salvation Army to the Catholics right around the world. And as I go and interact with other Christians, more and more I try to think not what's wrong with them but what's right with them, what can I learn from them. This book taught me to do that.

3. Right now I'm reading this book by Andy Crouch called Culture-Making.

It's been out a few years, everyone's been talking about it – I've just missed the party. But its brilliant because his thesis is that we've spent too long trying to relate to the culture, trying to be culturally relevant, even trying to change the world. And he says all of that is misguided.

What we need to do as Christians is make the culture with and for God.

And I love that thesis. Because ultimately the hope of the world isn't in us just having enough Christian teachers or enough Christian politicians. The hope of the world is that the people of God build communities that model the new kingdom in which different races, different ethnicities, different cultures, love one another across generations and across the divides. And show this is how we can do life. And so church isn't just some religious club. Church is us ganging up together to say: what could the world look like if Jesus is Lord and to do so in a way that others would look at us and go "Wow, that is the great unspoken dream of my life to be part of something like that." And evangelism and all those things are just a secondary result of us living in this way. This book talks intelligently and in a way that I think is important for the church about how we make culture. All authors think their book is important. But there aren't that many books that are really important. This book, I think, is an important message for the church at this time and I'm loving it. I don't agree with all of it – but that's half the fun of reading.

Inspired by Pete I went home and dusted off my copies of both Alan Paton and Andy Crouch, determined not to be a Bonsai believer.

Dr Krish Kandiah is the founding director of Home for Good and the executive producer of 'Books for Life', a new initiative to encourage the church to recapture reading as a spiritual discipline. Find out more at www.booksforlife.uk.