A lawyer charged with impersonating a Judaic studies professor online took the witness stand in his defense Monday, offering jurors a history lesson on the Dead Sea Scrolls and arguing his attempts to defend his father's lifelong research on the ancient texts weren't criminal.

Raphael Golb doesn't dispute that he sent e-mails and messages under pseudonyms attacking his father's critics, but he testified his actions weren't illegal.

"These blogs were about a pattern of unethical conduct in this field of study," he said.

The case is about ancient history, but the accusations are quite contemporary. The 50-year-old lawyer and writer has pleaded not guilty to identity theft, criminal impersonation and other charges related to his online posts.

Golb, a gaunt man with wiry brown hair, is a brainiac who graduated from Oberlin College, studied in France on a Fulbright scholarship and earned a doctorate in comparative literature from Harvard University and a law degree at New York University. His expertise is in linguistics and real estate law, he's working on a book and he's fluent in several languages, according to trial testimony in Manhattan.

Golb spent the bulk of his life around the scroll research and debate because of his father, University of Chicago professor Norman Golb. The scholarly debate is over the ancient Jews who wrote the scrolls, which are more than 2,000 years old and have provided important insight into the history of Judaism and the beginnings of Christianity.

Many academics say the scrolls were assembled by a sect known as the Essenes. Others, including professor Golb, say the writings were the work of a range of Jewish groups and communities.

Golb said he believed that his father's work, which includes a book called "Who Wrote the Dead Sea Scrolls?" has been stolen in part by a rival professor, Lawrence Schiffman, and that his research was being wrongly discredited, so he took to the Internet to avenge him.

"I was aware of my father's feelings of being violated," he said. "They were constantly making nasty remarks about my father."

Schiffman, chairman of New York University's Skirball Department of Hebrew and Judaic Studies, told the jury earlier that he and Norman Golb have long disagreed, albeit cordially, about the issue. But the disagreement so angered Raphael Golb, prosecutors said, that he mounted an elaborate, cloaked effort to promote his father's side by creating aliases and then crafting blog posts and e-mails to tarnish Schiffman's reputation.

Golb testified that he made up all the names he used in his Internet debates, even if they were names of real people who were tangentially involved.

He said he wrote an e-mail under Schiffman's name as a parody to highlight his outlandish and wrong-headed actions, including stealing from his father's research without crediting him.

"I never intended anybody to believe that these e-mails were sent by Larry Schiffman," he testified.

Golb gave a heady, lengthy testimony Monday, full of philosophical ideas about access to the scrolls and which theories have been promoted in the press and in the academic community around the world. He invoked the French Enlightenment philosopher Voltaire and the early 1900s Portuguese poet Fernando Pessoa as inspirations for his posts.

"I used methods of satire, irony, parody and any other form of verbal rhetoric that became the type of language used by philosophers during the Enlightenment to expose the irrational arguments of their opponents," he said.

The Dead Sea Scrolls, found in the 1940s in Israel, include the earliest known versions of portions of the Hebrew Bible.

Golb testified about what he called the difficulties his father had studying the scrolls because of strict rules allowing a select few scholars unfettered access to them and the fact museum exhibits now highlight only one side of the scroll debate and exclude other thoughts.

"My purpose was to expose the pattern of unethical conduct in the field of studies in its various forms," he said, citing exclusion of professors, plagiarism, smearing and a lack of access.

Golb said his criminal prosecution is fueled by Schiffman, who's angry about being called a plagiarist. When questioned by defense attorney David Breitbart, Golb said he didn't initially tell police the whole truth when they arrived to arrest him because he was scared.

"I asked myself whether there was some law I had violated, and I rapidly decided no," he said. "I had accused someone of plagiarism ... these are simple matters, not criminal."

Golb's testimony was to continue Tuesday.