Barbra Streisand hand-picked Mandy Patinkin for this movie, and he politely declined several times because he did not like the script. He was eventually invited to Streisand's house where they could discuss the parts he wanted to change. He then agreed to be in the film.
Though Yentl is much younger than Avigdor, Mandy Patinkin was only 30 years old at the time and Barbra Streisand was 40.
Some reviews claimed that all the songs sounded the same. In response, songwriters Alan Bergman and Marilyn Bergman said they wanted the songs to reflect the lessons of the Talmud, in which each lesson often reflects the lesson before it.
Barbra Streisand had the movie filmed in long takes without cuts because that's what she was used to with her background in theatre.
As early as 1971, Barbra Streisand wanted Ivan Passer to direct the film, but after reading the screenplay he declined, because he thought Streisand was too old and too famous for the part. Passer also thought the story was too unrealistic and told her, that audiences traditionally never accepted women masquerading as men in movies, reminding her of Katharine Hepburn's disastrous Christopher Strong (1933). While all of Passer's arguments were convincing, Streisand continued to develop the project and would later direct herself. Ironically, it became a big hit. [from: "Barbra Streisand: A Biography" by Ann Edwards].