Ask most people what the most significant technical innovation has been in the history of Christendom, and I would confidently guess that most would say it is the printing press. The widespread availability of both the Bible and other Christian writing, allied to the growth of formal education and rising levels of literacy, has been transformative in the scope for growth and learning that has been afforded to everyday followers of Jesus.

As I write in my study, there is a shelf behind me with ten different translations of the Bible. And for the last 30 years I have read the Bible every day with the aid of Scripture Union notes, and have also always had some form of Christian book ‘on the go’, aiming for a healthy mix of theological slant and subject matter. I do not know how I would begin to measure the impact of this reading on my spiritual formation, but I believe it has been substantial, and – honestly – probably more formative in my understanding of God than preaching has been. Moreover, I say that as someone who myself preaches regularly.

However, another technical innovation that is shaping God’s people, is much more recent: podcasting. Apple’s iPod was launched in 2001, initially as a music player, but in June 2005, the company released iTunes 4.9, which featured native podcast support. The growth in the format seems to have ramped up particularly in the last ten years, with popular shows including ‘the rest is’ format (with podcasts on entertainment, football, history and politics) and the News Agents, the latter demonstrating the power of the medium when Emily Maitlis and Jon Sopel chose to forego the platform the BBC afforded them to broadcast exclusively on a podcast.

There is much that is good about podcasts. The quality and choice of audio content can be superb, and I’m frequently struck at the fluency and accessibility of academics, journalists and pastors as they unpack the matters on which they are experts, often combining – sometimes seamlessly – analysis and insight with banter and humour. The downside of course is that we all choose what we want to listen to, and the list of podcast subscriptions we curate can be as much of an echo chamber as our social media feeds.

However, the issue that really vexes me about the explosion of podcast popularity is the extent to which they can remove silence from our life. The printing press was undoubtedly a remarkable innovation. But it’s only in the last 20 years that followers of Jesus have been able to channel personally chosen audio content straight into their ears – in the car, on the train, when walking or running – and I wonder what the tipping point is for many of us in terms of when that shifts from helpful to unhelpful, or even from healthy to unhealthy.

It seems to me that there are two challenges here. The first is the assumption that to grow in Jesus we always have to be taking in ‘content’ of some kind. Don’t get me wrong: among the ways we are being transformed is by the renewal of our minds, but how much content can we all properly assimilate? If we take in five or six sermons a week, does all that input genuinely feed us or do we suffer a kind of gluttonous excess? When does the content then get space to breathe and grow inside us?

But secondly, and perhaps more importantly, if we really believe that the goal of the Christian life is to grow in transformation and the deep, personal and relational knowing of God – rather than an abstract knowing about God – then what is the risk that reducing silence in our lives is actually shutting God out rather than inviting him in?

Mother Teresa said that “God’s first language is silence, and everything else is a bad translation”, but silence is something I suspect many activist evangelicals find more uncomfortable than they would care to admit. The minds we think are so disciplined can wander in a random way that surprises us and in church contexts where the size of the task before us and the number of the lost is so great, what is productive about silence?

Yet the Psalmist tells us to ‘be still and know that I am God’, and God himself in human flesh regularly sustained his earthly ministry by withdrawing alone to a quiet place. Jesus’ pattern shows us that God does not only speak in ‘content’ – in Scripture, sermons, books and podcasts – but he speaks also in solitude, in slowness, in creation, in quiet moments of conviction, imagination and revelation. Furthermore, when we are in the presence of those who know us best and love us most, we should be entirely comfortable, even when there is nothing to be said.

In the last year of my father’s life, when he was very infirm and must have had a sense that death was near, my sister walked in on him one day as he was sitting in his armchair, simply staring into space. Despite his love of news and culture, the TV wasn’t on and nor was the radio, and there was no book in his hand. She asked him what he was doing and he replied ‘I’m just thinking my thoughts.’

A carefully measured number and choice of podcasts is helpful to Christian growth, but if we listen so much that we shut out silence they may stifle the very growth we crave. For whatever modern media we have to hand we must never forget the timeless truth that Jesus and the Spirit together will often do their most significant work in silence and stillness, in the thinking of our thoughts, the baring of our souls, and the daydreams and disappointments of those that hunger and thirst after righteousness.