I imagine that you don't spend very much time thinking about John the Baptist. Understandably - he's an obscure character from a very old story.
But when you do stop to think about him, I wonder how you picture John the Baptist in your mind's eye: perhaps as a bit of an oddball, a wild man walking barefoot in the desert, with unkempt hair and shocking clothes, and eating habits that probably meant that when he opened his mouth to begin one of his uncontrolled rants, the air around him smelt bad.
John's place in history is undisputed. He is down as the chief witness to Jesus Christ. He's the one God chose to explain to the waiting world just who Jesus was and what he was likely to do.
I don't know about you, but if I ever need to find someone to witness for me, I'd be looking for someone respectable, someone with a bit of influence, a professional of some sort. Stood next to a city councillor or a head teacher or a bishop, John the Baptist with his hair and halitosis, looks like a very unreliable witness.
Yet, here is one of the strange ironies of the Christian faith, one among many we remember at this time of year. God chooses unreliable witnesses to reveal the truth to the world. The people least likely to be listened to by polite society, are precisely the ones who hold the key to real understanding.
I invite you to consider whether that's true today as it was in John's time. I suggest it is. After all if you want to find out the real truth about, say, the goings-on in Prince Charles's household then you won't get it from the Buckingham Palace Press Office - you're much more likely to hear it from the family and friends of those who've been victimised.
If you want to find out what it's really like trying to seek refuge in a foreign country, then you'll get a far better impression by spending an afternoon with an asylum-seekers project than by reading the Daily Mail. The scraggy Big Issue seller - who actually reminds you a bit of John the Baptist when you look at him - may rant on about the uselessness of the benefit system for people like him, but he's worth listening to because he's educating you, far better than a textbook, about the realities of living in poverty in Britain today.
Unreliable witnesses turn out to be truthkeepers. Of course, we must learn to discern what they're saying. For example, we may consider that Marilyn Manson has a lot of right things to say about the abuses of religion and the violence of the American Way, but we must ask ourselves about the value of the alternative world that he conjures up, where abuse and violence still seem to reign.
So here's an unusual Advent message - let's tune our ears to hear the voices that usually get censored, covered up, the odd voices like John's. Let's learn to discern them, to sift out those which lead down blind alleys and keep hold of those which offer new enlightenment about our world, new insight into our lives. Like those who took John seriously, we may find we can see things far more clearly because of what these witnesses say.