BERLIN - Joachim Gauck, a Protestant pastor and anti-Communist activist from former East Germany, was sworn in on Friday as Germany's 11th post-war president, promising to use his experience of tyranny to stand up to the far-right and other extremists. The election of 72-year-old Gauck last Sunday has raised hopes that a charismatic figure of such ethical stature can revive faith in a post which is largely ceremonial but symbolically important for Germany following his predecessor's ignominious exit. "I would like to ask you all for a gift: your trust," Gauck said in a moving speech to the Reichstag, the German parliament which was set on fire on 1933 and bombed in World War II. Chancellor Angela Merkel and lawmakers from across the political divide warmly applauded the president's maiden speech. Despite their shared history - Merkel is the daughter of an East German pastor and grew up under communism - she opposed his first candidacy in 2010 in favour of her conservative colleague Christian Wulff. Wulff quit last month in disgrace over a probe into his personal finances and favours from business contacts. This time Merkel had to accept Gauck, who is not affiliated to any party but was put forward by the opposition centre left and supported by even the chancellor's own Liberal allies. Gauck poses no threat to Merkel's domination of national politics, but his moral authority, independence of mind and lack of party affiliation could make him an awkward partner for her government as it struggles to overcome Europe's economic crisis.