In The Guardian on Thursday there was a full page advert from a firm of bookmakers setting out odds on what would happen in the second party leader debate on TV that evening, from who would speak when to how many times Gordon Brown would say 'I agree with Nick'. This might set a trend for fund-raising in church, where you  take bets beforehand on what the sermon would be on and how many times I would say 'finally' before actually stepping down from the pulpit...

So what might we reflect on this morning, coming out of the long and varied scripture readings?  I want to touch on three things that have been around this week in our national life: the ash cloud from Iceland; the election and how to vote; and St George's Day – all in the context of Easter and the resurrection, and all in less than 10 minutes.

There is one thing which today's readings have in common.
The story of the Flood is about a great natural disaster which almost destroys humanity. The world is coming to an end, and Noah and his family have to find a renewed hope, not saved from the Flood but saved through it.
The story of Tabitha from Acts chapter 9 is about death on a much more intimate scale, the death of a friend who did good things for others and who was good at sewing too, but now is gone.
In John 10 Jesus faces a hostile crowd who want to kill him by stoning him, because he holds true to his relationship with God and with his disciples.

But note in all three of these readings the importance of the idea of the sign: the sign that God is at work in the world. It's an explicit sign in Genesis, where God puts the sign of the rainbow in the cloud as a reminder of his commitment to human beings. Remember that just because they lived a long time ago, ancient people weren't stupid: Greek philosophers wrote about the physical cause of rainbows, and they could see rainbows in glass or in a waterfall. When Genesis speaks about the rainbow as a sign, it doesn't mean that the Hebrews thought that God invented the rainbow for them, and of course we now know that it's 'just' the refraction of sunlight through drops of water. What it means is that God has invested the rainbow with this significance: that when you or I see the rainbow, it's a sign to recall us to the faith that God loves us and is at work in the world.

When Peter comes and heals Tabitha by raising her back to life, he's not curing her from all her sickness for ever – she will still die; nor is Peter claiming that everyone who dies can be brought back to life. What happens here is a sign that Peter follows the risen Jesus, who brings life to all, and that Jesus calls everyone to follow him. Tabitha's healing is not remembered because it was a good thing for her, or because the ladies of Joppa wouldn't have to find a new dressmaker, but because it was a sign to the people of Joppa who turned to follow Jesus.

When Jesus faces the crowd in the Temple, he appeals to the works that he's done, the signs which are told us in John's gospel that we might believe, signs of healing and other miracles.
In all three readings, the events point beyond themselves to the power of God at work in Jesus Christ, seen supremely in the resurrection, but also at work in the world then, and equally at work in the world now.

in Thursday's Guardian, as well as a bookmaker's advert, there was an interesting and scary article about volcanoes. They regularly cause major climate change and disruption to life on earth. Only 70,000 years ago there was a massive volcano which nearly extinguished all human life; a big eruption in 1783 produced ash which cooled the world down and led to crop failure, starvation around the world, and indirectly to the French Revolution. When Yellowstone Park finally erupts again it will wipe out most living things in North America.   Last week's volcanic ash is a sign for us: a sign of our fragility, of our pride and complacency and vulnerability in a world which we can't actually control: a sign which should like the rainbow point us to faith in God who is greater than all these things. We have taken the mystery out of the world by turning rainbows into scientific objects, rather than finding God in the signs that litter the world.

On Thursday week most of us have the opportu­nity to make the sign of the cross against people's names in the election. It will be taken as a sign of trust in the person we vote for, even if it isn't. Elections are a sign of the fragility of human power, and our accountability not only to others but also to God for how we use our power – as the Civic Service in the Cathedral later this year reminds us. How should we vote? I really don't know: but I'm sure that we should vote motivated by faith in God and God's compassion, rather than by self-interest. A cross in a voting booth is also a sign: let's think and pray and make it a sign of God at work in the world.

And today too we remember that we don't fly the flag of St George in church to show that we're English, as if we're football supporters – it's far more precious than that; we lay it on the altar and dedicate it because it's a sign of God at work in our civic and national life, the God who is there to support us and confront us and to make us more like Jesus in our dealings with one another. The growth in support for St George's Day is in some ways a sign of our uncertainty about what it is to be British, and what being English actually means – can the BNP for example cope with the fact that many English people and British workers have brown or black skins? But as with voting, so with the flag of St George: let's be proud that the sign of our national saint is also the sign of the Red Cross that helps those in need, and that our national flags consist of the signs of the saints of the God who is at work today in this frightening and exciting and wonderful world.

Signs? We too are called to be signs of the work of God in the world, wherever and with whoever we may be...