When was the last time you felt truly thankful? Maybe you're American, and the idea is at least built into your annual calendar. Or perhaps like me, you occasionally stop for long enough to look at the life you've been given and realise just how many good things it contains. Perhaps also you've had an encounter with someone else whose own tragedy makes you reflect on the things you sometimes take for granted; maybe you've just watched awful scenes unfold on the evening news and quietly thought "thank goodness that's not me."

For most of us, the constant cut and thrust of everyday life means we don't often allow ourselves time to feel and express thankfulness. We're so focused on the new things we hope to achieve, or obtain, or do, that we relegate gratitude for the things we've already achieved, obtained or done to a nice thought we should probably have sometimes. It's the same with prayer; we try so hard to make thanksgiving a major focus of our conversations with God, but in reality we often descend quickly into a list of requests. It's not that we don't feel thankful for the things God has already done, it's just that all the new problems feel so pressing.

Practising gratitude is a discipline, and like all disciplines it requires our personal investment. You're probably familiar with the idea of a 'Bucket List'; the practice of writing down all the things you want to do before you die (or, kick the bucket). These usually include a mix of exotic destinations to visit, out-of-the comfort zone activities to try, and perhaps people to meet. A less pessimistic version is the 'things-to-do-before-I'm...' list, which many people make in the panicky year approaching a milestone birthday. They're a great way of focusing on future aims, but they still exist firmly in that culture of achieving, obtaining and doing more.

What I want to propose is a sort of reverse bucket list, which I'm crudely going to call a 'Done-It List.' Instead of writing out all the things you want to do and get before you die, you chronicle things that you've already done; things for which, when you think about it, you feel truly thankful. That might seem like a fairly wide definition, so (once you've grabbed a pen and paper) let's break it down a bit:

Places

Where have you been in the world, or in the country in which you live? What are the great places that you've visited, homes or hotels that you've stayed in; what are the extraordinary places you've stood in and felt a true sense of awe and wonder? Write them on the list.

People

Who are the people you're thankful for having met and spent time with? Who are the great friends with whom you've built deep, rewarding relationships? Who are the heroes who you've caught a glimpse of / shaken hands with? Add their names, and why you're grateful for them.

Achievements

What are the things you've done that you're proudest of? In education, work, family, sport and other interests? Forget what you're aiming for momentarily; what markers have you already passed on the journey? Write them down, even if they seem quite small in hindsight.

Faith

It's a great spiritual discipline to meditate on the work that God has already done in us. So ask yourself: what change has already taken place in me? How have I already grown spiritually; how has my faith deepened since I first 'said yes' to God?

Possessions

It's not wrong to have stuff - but our relationship with the things we own can sometimes be unhelpful (or even idolatrous). So with that note of caution in mind, what are the things you're really glad you own? Your home? Your loveably idiosyncratic car which only starts on the third try? Your music or film collection? What have you already obtained for which you're thankful?

Moments

Finally, what are those memories which don't fit neatly into one of the other categories, but which would feature on the highlights reel of your life? The moments where you suddenly felt fully alive; where you had an epiphany or what some people call 'Kairos' experiences where suddenly time seems to have an extraordinary depth and meaning. They don't need to have been a spectacular sunset; one of mine took place in a car rental office in LAX airport. Add these to the list too.

I guarantee that this action will foster a sense of thankfulness within you; perhaps a slightly more positive reaction than reflecting on others' misfortune with gratitude that by comparison, our lives are ok.

Thankfulness is really important. It's encouraged and commanded biblically, but my hunch is that God doesn't need that from us; rather he knows that expressing gratitude is important because it's good for us. It prevents us from becoming obsessed with the ultimately unfulfilling pursuit of acquiring more, and it helps us to feel something far better: contentment. 

Martin Saunders is a Contributing Editor for Christian Today and the Deputy CEO of Youthscape. You can follow him on Twitter: @martinsaunders