Earlier today before a crowd of over 23,000, Pope Benedict said that the theme of slavery, found in many of the Psalms, helps show the anticipation of Christ’s salvation which the Church waits for during Advent.

After a brief hiatus into St. Paul’s letter to the Ephesians last week, the Pope returned today to his ongoing catechesis on the Psalms, this time, discussing Psalm 136, ‘on the rivers of Babylon.’

He said that "On this first Wednesday of Advent,” the Church waits in the “liturgical period of silence, vigil and prayer in preparation for Christmas.”

The Pope explained that Psalm 136 “evokes the tragedy experienced by the Jewish people during the destruction of Jerusalem in 586 BC, and their deportation to Babylon."

"This heartfelt invocation to the Lord to free His faithful from slavery," he said, "also expresses the feelings of hope and expectation of salvation with which we began our Advent journey.”

Pointing out that “the backdrop to the first part of the psalm is the land of exile with its rivers and canals, the rivers and canals that irrigated the Babylonian plain where the Jews had been deported,” the Pope called this imagery an almost “symbolic foreshadowing of the death camps in which, last century, the Jewish people underwent the infamous operation of extermination that has remained as an indelible mark of shame in the history of humanity."

"God,” he went on, “Who is the ultimate arbiter of history, will know how to understand and accept, according to His justice, the cries of the victims, despite the harsh tones they sometimes assume.”

Pope Benedict also turned to the writings of St. Augustine to help elucidate the text, saying that in his meditation on the Psalm, "the great Father of the Church introduces a surprising note: he knows that even among the inhabitants of Babylon there are people committed to peace and goodness, though without sharing the biblical faith.”

“In the end, then,” Augustine suggests, “God will lead those people to the heavenly Jerusalem, rewarding them for their pure consciences."

He said that, "God will not allow them to perish with Babylon, having predestined them as citizens of Jerusalem, on the condition, however, that, living in Babylon, they do not promote its pride, its grandeur or its overweening arrogance."