It was said of the German philosopher Immanuel Kant that his habits were so regular that people could set their watches by his appearance on his daily walk. So it is with Handel’s “Messiah” in Boston: By its appearances in Symphony and Jordan halls, ye shall know, it is Christmastime.

This is, by and large, a happy tradition. But as regularly as the concerts return, so does the vexing question of how to keep the musical experience vital. This year marks Boston Baroque’s 32d season of “Messiah” performances. Music director Martin Pearlman has said that for him, that renewal comes not from trying to find a different conception for the piece each time, but from mining the score for fresh details and new depths.