I really appreciated Adrian's blog post on the importance of guarding the heart – thanks Adrian!. As I am involved with training preachers on the PT Cornhill Training Course, I see more and more how vital our hearts are as preachers. As well as Thomas a Kempis, I have benefited greatly from John Flavel's 'Keeping the Heart' which the good folk at Christian Focus have re-published in a very accessible format. Here's how Flavel kicks off:

'The heart of a man is his worst part before it is regenerated, and the best afterward; it is the seat of principles, and the foundation of actions. The eye of God is, and the eye of the Christian ought to be, principally fixed upon it. The greatest difficulty in conversion is to win the heart to God; and the greatest difficulty after conversion, is to keep the heart with God' (p 7).

The Puritans used to talk about the need to hold orthodoxy (correct doctrine), orthopraxis (correct actions) and orthocardia (correct heart) We tend to think a lot about the first two of those. If you want help with the last one – orthocardia – Flavel is a wonderful heart surgeon.

More like this:

• John Owen and the Barn
• In Praise of John Flavel