(Former East German rights activist Joachim Gauck, the joint candidate of the government and opposition for the post of president, at the Chancellery in Berlin February 19, 2012. REUTERS/Thomas Peter )

Joachim Gauck, a former anti-Communist human rights activist in East Germany who is set to become the next German president, is a moral authority to be reckoned with. The Lutheran pastor, who has been called Germany’s answer to Nelson Mandela, was one of a number of Protestant clerics who helped bring down the communist East German regime, setting the stage for the fall of the Berlin Wall and reunification in 1990.

The 72-year old, who is married and has four children, ran the state-run archives on the Stasi after reunification and earned recognition for exposing the crimes of the dreaded East German secret police. Even after his retirement in 2000, the author of many books continued his campaign for human rights. His new book, “Freedom — A plea,” hits stores nationwide on Monday.

Perhaps Gauck’s very moral gravitas is one reason Chancellor Angela Merkel passed over him in 2010 for the presidency, before being pressured into nominating him on Sunday – he is a formidable rival for Germans’ affections.

Already two years ago and despite Merkel’s opposition, he was the public’s firm favourite for the presidency. Media across the political divide backed him, with mass-selling daily Bild running a picture of him on its front page next to the headline “Yes we Gauck” — a twist on the U.S. President Barack Obama’s campaign slogan “Yes we can.”