I was once in a Jewish youth group and we had a Rabbi attend a session. He asked a simple question: why are you a Jew? The standard answer because of my mother was excluded. Why else? There were many answers. Because of the Holocaust. Because of anti-Semitism. Because of the constant attacks on Israel. All fine answers, the Rabbi said, but interestingly they all dwelt on the negative. No one answered because of the joy of the Festivals and Sabbath. No one said because of the history and culture. No one said because of the link between the past, present and future. In other words, no one looked at the positive reasons to Judaism. It's a lesson that stuck with me, even as I grapple with the great concepts of God and religion. Since that time I've always been conscious of it, that Judaism is something to celebrate and not just defend.

Soon Yom Kippur begins. This Day of Atonement is something of a misnomer - as I mentioned previously the entire period between Rosh HaShannah and Yom Kippur is a time for atonement but also reflection and looking forward to the year ahead. Yom Kippur represents only the final part of that process. It is the day where the looking back stops and the looking forward begins.

Yom Kippur involves fasting for 25 hours (and forgoing certain other life-and-death events). No drinks, no water, no food. Yet surprisingly it is only a minor part of the festival and not the focus at all. So long as you prepare properly hunger and thirst do not become issues. The preparations are simple: avoid salty foods and caffeine, eat only moderate meals and make sure you're well hydrated before hand. Like all Jewish festivals there is food - the celebratory feast at the end. But that's a whiles away and there is much to do before then.

Tonight's Kol Nidre prayer is the most solemn in all Judaism. Tomorrow evening the final service, lasting about an hour, involves a final pleading to God to inscribe us all in the Book of Life before finishing with a final blow of the Shofar (ram's horn). Traditionally God shuts the Book at the end of this final service and the fates are sealed for a year. Some consider that God pays particular attention to this service, replacing Elijah in sitting in every congregation (he is God, after all, so he can get around) and watching Himself. Others say the shule becomes like the Holy of Holies in the Temple in Jerusalem, the holiest place in Judaism. Even most irreligious Jews make the effort to attend Kol Nidre and this final Nilah service. Call it the insurance service.

Back on Rosh HaShannah I asked you to think about the year past and the year ahead. It is one thing to say "I'm going to be a better person this year" but it also completely useless. When one takes stock of your life it is all to easy to gloss over the faults and dwell on the good. It achieves nothing. What is vital is to take an honest look at yourself, warts and all, and decide on a firm action plan to improve what you don't like AND to keep what you do. Yom Kippur represents the final day of the 10 day process of doing just that. It is not the end; you cannot wake up tomorrow and forget. Instead Yom Kipper marks the end of the period of thinking and marks the beginning of the period of doing. It's time to take the action plan and start implementing it. That's not to say the plan cannot be amended or improved upon during the year. But it does mean it is time to move from theory to practice, from why to how. And that's the hard part. So you can use Yom Kippur to help you make that transition by thinking about all you've reflected on from the past 10 days and spend the next 25 hours (fasting optional for non-Jews) thinking about how you're going to make it work.

At the same time it is a good time to take stock of the wider world around you. This is a world where this can happen, or this, but also where good deeds can be done like this, and where there is hope and lessons learnt. Likewise within all of us there is the constant battle between bad and good. Yom Kippur represents the time where you close the books on that battle for the year just passed and prepare for it for the year ahead. Just like the world itself, it is a never-ending battle that must always be fought. How you play that battle will determine what you do about the world you in live in, the people you live with and the things you do about it.

It's worth thinking about for at least one day a year. It is yet another wonderful reason to be Jewish. Because for one day a year you are forced to confront it all and deal with it, where it can be far easier to avoid and simply live without living. Because our way of life in this enlightened modern era of plenty and freedom is something to be celebrate, not just defend.

Others: Joe at WoC; First Things First; Rachel Ann with some others to think of and pray for too; Kesher Talk on preparing for YK.