A rainbow is seen in the sky as the Pope Benedict XVI pays his respect to the victims of the former Birkenau Nazi death camp in Oswiecim, southern Poland May 28, 2006. Calling himself 'a son of Germany,' Pope Benedict prayed at the former Nazi death camp of Auschwitz on Sunday and asked why God was silent when 1.5 million victims, mostly Jews, died in this 'valley of darkness.' REUTERS/Damir Sagolj