There is an old myth about an impoverished Jew who visited a rabbi to complain about his desperate circumstances: house full of kids, too much mother-in-law and not enough food or bedding to satisfy any of them. The story goes that the rabbi advised him to bring his farmyard animals into the house for a while, so that when he finally receives permission to eject them, he would appreciate the space and quiet.

(Incidentally, I never understood the legend. How was the pauper helped by the advice? He'd learnt that it could always get worse? So what? Did this knowledge in any way alleviate the actual chronic overcrowding? If you saw someone hitting his head against the wall just so he could report how good it feels to stop, would you automatically conjecture that this was a man following rabbinical advice or would you be more likely to assume that he'd forgotten to take his medication?)

In this week's Parshah we read how the Jewish slaves were commanded to bring a sheep into their hovels, keep it there for four days, and then slaughter it and smear some blood on the doorpost. Now I never grew up with animals around the house (Mum, if you're reading this, it's not too late to buy the dog we used to nudge for...) but my understanding about livestock is that they make less than perfect houseguests. Even if G‑d had wanted the Jews to prepare a sacrifice for Him, surely he didn't need to afflict them four days in advance?

Obviously the justification for their indoor animal husbandry was more than just helping the Jews appreciate their blessings. Like much of Judaism this was an exercise in conspicuousness. We brought sheep into our homes specifically so that our non-Jewish neighbors should witness and wonder.

The Egyptians used to worship sheep. To take their god, the object of their veneration and their icon of protection, and publicly announce one's intention to eat it took a special kind of conviction and courage.

We, too, are often called on to capture and slaughter the sacred cows of contemporary society. To live a life of religion and morality, to project faith in the face of the overbearing popular culture, demands strength of purpose and self-belief. This ability to stay true to one's convictions, rejecting the slings and arrows of trendy tyranny, is an ability we inherited from our forbears.

Just as their courage for G‑d, exhibited in a foreign land, proved them worthy of redemption, so too will we walk firm in our ways for now and until eternity.