Pope Benedict has returned to the Vatican after his symbolic act of contrition at Auschwitz.At the end of his four-day pilgrimage to Poland, the pontiff led prayers for atonement at the Birkenau monument near the infamous former Nazi death camp. The Pope said he sought reconciliation in a place of horror. The former cardinal Joseph Ratzinger was briefly in the German army at the end of the Second World War. He said: “In a place like this, words fail. In the end there can only be a dread silence, a silence which is itself a heartfelt cry to God: Why Lord did you remain silent? How could you tolerate all this?” The haunting Jewish prayer for the dead concluded a day of penitence.