With its breathtaking scenery and jaw dropping panoramic views, Keswick might seem like an odd place to be trying to encourage Christians to ask big questions about their faith. But I have come to the Keswick Convention 2014 armed with a multi-coloured sofa to encourage Christians to take a deeper look at their faith. I've been invited to run a series of seminars on my book Paradoxology. When I started writing it my intention was to write a book answering questions that Christians often ask about their faith. But the more I dug in, I realised I was writing a book about the questions that Christians almost never stop to ask.

Somehow from Sunday school onwards we rush past some very tricky ideas. Abraham gets off pretty lightly in most children's Bibles – a hero of the faith who was asked to murder his own son and came within a knife's stroke of doing it. I remember singing pretty loudly about "the walls coming tumbling down" from the story of Joshua, but there are some pretty harsh words about what Joshua's army were supposed to be doing to the inhabitants of Jericho once the walls had fallen. I want to encourage Christians to have the courage to look hard at the tough parts of the Bible for three reasons.

1. If we never look at the hard parts we are editing God down to size

Christians believe "All scripture is God breathed". That means all of it, not just the nice parts that suit us. The parts that back up our political leanings or those that we find comforting and we'd like to turn into a fridge magnet. It also means the parts that we don't like and don't fit neatly into our theological systems. We need to trust God enough to look at the difficult parts of scripture too.

2. If we never look at the hard parts we will not be fully equipped to face challenge or tragedy

There's a Chinese proverb I like: "The best time to plant a tree is 20 years ago, the second best time is now." In the same way, the best time to have worked through the tough questions in your faith is 20 years ago because then you will be better placed to handle the tough things in life when God doesn't do what we hope or pray for. But the second best time to work through the paradoxes and challenges in your faith is today.

3. If we never look at the hard parts we are going to be ill-equipped to help our friends find faith

So many of our friends need much more than the simplistic fridge magnet form of the Christian faith than what they are often offered. If we are going to be able to help them find faith then we will need to wrestle with the deep questions of faith alongside them.

This week at Keswick, surrounded by the beauty of nature, we are going to take a long hard look at some difficult questions to more fully appreciate the beauty and wonder of the God we serve.

Krish Kandiah is author of Paradoxology: Why Christianity was never meant to be simple (Hodder Faith). He is executive director of churches in mission at the Evangelical Alliance and founder of Home For Good, a charity exploring how the church can make adoption and fostering a normal part of church life .

Keswick Convention's mission is to unite with Christians around the world to commit to three big priorities for our lives and churches – hearing God's Word, becoming like God's Son, and fulfilling God's mission.