MAINZ, Germany — Cardinal Karl Lehmann is ending a 21-year tenure as president of the German Bishops’ Conference this month.

In a letter to the members of the bishops’ conference dated Jan. 14, the cardinal, who is also bishop of Mainz, said heart problems he suffered in December prevent him from continuing his work as conference president with the same strength as before.

The 71-year-old cardinal will continue as bishop of Mainz.

His resignation is effective Feb. 18, during the spring meeting of the German bishops in Würzburg. His successor will be elected at that time.

In December the Cardinal went to the hospital because of an irregular heartbeat. The curia in Mainz tried to play down the event. But Cardinal Lehmann then canceled all appointments around Christmas, an indication that his health was not too good.

The cardinal used to rush from appointment to appointment, and commuted regularly between Mainz, Bonn, where the bishops’ conference is headquartered, Berlin and the Vatican.

For many Catholics his resignation came unexpectedly. The “liberal voice of German Catholicism,” as the Frankfurter Allgemeine Zeitung calls him, has shaped the Church in Germany for more than two decades and became one of the most influential heads in the history of the bishops’ conference. A former assistant to Jesuit theologian Karl Rahner, the cardinal is himself a prolific scholar and author, as well as a professor of dogmatic theology with doctorates in theology and philosophy.

His election to the prestigious position of bishops’ conference head in 1987 was a surprise, as Cardinal Friedrich Wetter, then archbishop of Munich, was the “natural” candidate for that office.

The “close-to-the-people” bishop therefore quickly became a popular and highly-esteemed guest at conferences, jubilees, talk shows and lectures.

But his relationship with the Vatican remained ambivalent.

In a pastoral letter of 1993, written with two other German bishops (among them then-Bishop Walter Kasper), argued for admitting remarried and divorced Catholics to holy Communion.

He was also involved in heated discussions with the Vatican on the matter of Church involvement in abortion counseling. In Germany, women planning an abortion must first have counseling at a government-approved agency and obtain a certificate that such counseling took place.

In 1999 Pope John Paul II personally requested the withdrawal of the Church from the abortion counseling business, supported by the prefect of the Congregation for the Doctrine of Faith, Cardinal Joseph Ratzinger. Cardinal Lehmann obeyed.

Successor?

After the election of Pope Benedict XVI, public interest in the Catholic Church increasingly shifted from Mainz to Rome, and Cardinal Lehmann always tried to characterize his relationship with Benedict as good.

His stand toward Rome did not harm his popularity in Germany with its traditional anti-Roman feelings. A sign of this popularity is his re-election as conference president in 1993, 1999 and 2005.

“Karl Lehmann has become something like an institution,” acknowledged Cardinal Kasper — his close friend — at Cardinal Lehmann’s 70th birthday party last year. The cardinal’s pupils hold chairs at universities, episcopal sees (e.g. Bishop Gerhard Ludwig Müller of Ratisbonne/Regensburg) and important ecclesial decision-making positions.

Cardinal Lehmann is in very good contact with the world of media, politics, economics, science and culture. He used his position to make the Church present in all areas of public life.

For some critics he went too far, for others he didn’t go far enough.

It was a particular challenge for Cardinal Lehmann to unite the various groups within German Catholicism. Under his guidance, the presidency became by far more important than in many other countries in the Catholic world.

Who will succeed him? Germany’s episcopate has undergone a strong rejuvenation lately, but traditionally the presidency is held by either the archbishop of Cologne or archbishop of Munich. Cardinal Joachim Meisner of Cologne, at 76, seems too old for that function, and Bishop Reinhard Marx of Trier, top candidate for the presidency, just began another job — he was installed as Munich’s Archbishop on Feb. 2.

Unless he gets elected, an interim candidate (for six years) will be elected.

Robert Rauhut is based in Munich.