Millions of Jews, if they are paying any attention at all at the Seder, must have wondered from time to time what is meant by the Haggadah when it 'explains' the words ובזרע נטויה (with an outstretched arm) by the comment זו החרב (this is the sword). Sure, it quotes a verse proving that an outstretched arm can hold a sword and, indeed, the imagery is clear enough anyway. G-d isn't holding up His arm to play baseball. But once we have solved the question of how the midrash works, we still have to …