Sha'arei Orah, or Sefer HaOrah, (‎שערי אורה‎) is Joseph Gikatilla's most influential work. It discusses 300 ‎names of God and is organized into ten chapters, one for each sefirah. Each sefirah has one main ‎name but may have many others. Some names are associated with more than one sefirah. The ‎Arizal called it "a key to understanding the mystical studies." The Vilna Gaon and Zundel Salant ‎recommended that their students study it.‎