Rabbi Philip Berg, whose Kabbalah Center International put a modern spin on an ancient Jewish mystical tradition, attracting celebrities like Madonna, Demi Moore and Britney Spears but also incurring criticism on spiritual and financial matters, died Monday in Los Angeles. He was 86, according to the center, although some news reports put his age at 84.

His death, from respiratory failure and pneumonia, was announced by the center.

A former insurance salesman, Rabbi Berg established the center in Queens with his second wife, Karen, in the early 1980s. The Los Angeles branch, now its headquarters, opened in the mid-1980s, and there are now branches in some 40 cities worldwide.

The rabbi suffered a stroke in 2004, and since then the organization has been led by Mrs. Berg and the couple’s sons, Yehuda and Michael.

In an e-mail message to The New York Times on Thursday, Madonna wrote of Rabbi Berg, “I learned more from him than any human I have ever met.”