This is the origin of the idea of the scapegoat. There were two goats as part of this ritual, one for God and one to be sent away called "Azazel". The Azazel goat that is sent away to absolve all the sins of the people in this compelling and strange ritual is a very powerful, and almost sinister, symbol.

The legacy of Azazel might mean that we would have inherited a great fear of goats. Yet goats pop up all over Jewish folklore. Perhaps because they were such a common sight tethered to so many gateposts in our homes, they feature frequently in the Jewish imagination in warm, positive and sometimes mystical terms.

Whether bringing almonds and raisins to the cradle in Abraham Goldfaden's lullabies, smiling mysteriously as they float in Chagall paintings, or silently leading the questing Jew to the Holy Land in Agnon's stories, goats are humble, friendly creatures, part of the Jewish family.

Jews have also often been stereotyped as the scapegoat for the world, accused wrongly and unfairly blamed for problems not of their making.

So what are we to make of Chad Gad Ya, the song that concludes the Haggadah, all about "just one kid, that the father sold for two zuzim"?

Despite its likely German folksong origin, the kid in Chad Gad Ya has been interpreted widely as symbolising the oppressed Jewish people, which was bought by the father (God) for two coins (Moses and Aaron). The subsequent players in each verse represent the nations who persecuted the Jewish people over the centuries: the devouring cat represents Assyria; the dog – Babylon; the stick represents Persia; the fire, Macedonia; the water is Rome; the ox, the Saracens; the ritual slaughterer and the Angel of Death, the Turks.

But we end the song in hope. God destroys the foreign rulers of the Holy Land and vindicates Israel as "the only kid". So the scapegoat of the world survives and is finally claimed and embraced in safety by its Maker.