R. Israel Ba'al Shem Tov did not leave any works either in his own hand or signed by him, nor are there any contemporary portraits of him. However, several letters bearing his name have been published: to Abraham Gershon of Kutow (Ben Porat Yosef), to Jacob Joseph of Polonnoye (Shivhei ha-Besht), to Moses of Kutow (Buzina de-Nehora, 1880), to an anonymous individual (Shivhei ha-Besht), and to R. Meir av bet din of Staro-Konstantinov (Responsa Mayim Hayyim). Various fabrications exist. In 1919 a package purporting to be documents from Israel and his disciples was found in Kherson, U.S.S.R. which had allegedly come from the government archives in Kiev where documents were preserved regarding the trial of Israel of Ruzhin, charged by the government for instigating the murder of an informer. Apparently, however, all these documents are forgeries or copies of works that had been previously published.

The Ba’al Shem Tov did not put his teachings into writing and even opposed the attempts of others to do so. Only 20 years after his death, his disciple, Jacob Joseph, presented in three of his own works-Toledot Ya'akov Yosef, and Zafenat Pa'ne'ah and Korets, 1782—hundreds of sermons and homilies which he had learned from the Ba'al Shem Tov. At the end of Toledot Ya'akov Yosef there is a collection of Israel's sayings, and the author comments: "These are statements which I heard from my teacher and I only took down fragmentary notes because I was afraid both of writing everything and also of forgetting it." Other disciples and their disciples included in their works statements which they had heard from him or which had been cited in his name. Aaron b. Zevi Hirsch ha-Kohen of Opatow (Apta) claimed to have collected all the statements of Israel which had appeared up to that time in his Keter Shem Tov (Zolkiew, 1795), but most of his quotations are from the works of Jacob Joseph. The book Zavva'at ha-Ribash of Isaiah of Janow (1794) does not include the testament of the Ba'al Shem Tov, but only a selection of his statement, and according to Shneur Zalman of Lyady, who had collected the statements, did not understand their meaning. Most scholars contend that the work mainly includes teachings of the school of Dov Baer, the Maggid of Mezhirech, but this needs further study. The most complete and best anthology of Israel's teachings is Sefer Ba'al Shem Tov (Lodz, 1938), edited and arranged by Simeon Menahem Mendel Wodnik.

The legends about the Ba'al Shem Tov have distorted his historical character. Formed even during his lifetime, the stories about his miracles became an integral part of the hasidic atmosphere and both increased the admiration for him and stimulated his opponents. Disciples who had come in contact with him and his family were among the first to assert his supernatural qualities. But people who were not among his close associates also at times told of his charismatic personality, even during his lifetime. Thus there developed a literature of shevahim (lit. "praises"). The first anthology of legends was Shivhei ha-Besht, compiled by Dov Baer b. Samuel of Linits, the son-in-law of Alexander Shohat, who served for several years as Israel's scribe. The collection was copied many times and hence was full of errors. Only after the compiler's death was it printed as Shivhei ha-Besht by the publisher Israel Jaffe, a disciple of Menahem Mendel of Vitebsk and Shneur Zalman of Lyady. Jaffe proofread the anthology, removing distortions which in his opinion resulted from copying. He rewrote the first chapter on R. Israel's birth, youth, and revelation according to the tradition given by Shneur Zalman. Thus Jaffe must be viewed as the second author and editor of the anthology, and his edition, printed in Kopys (Kapust) in 1814, has been accepted as the basic one; all other editions are based on it, with only slight changes. In that year the second book was printed in Berdichev and the third in Laszcz\w. Similarly, two editions appeared in Yiddish (Ostraha (Ostrog) and Laszc\w) which differ greatly from the Hebrew edition. The reciprocal relationship between the Hebrew and Yiddish versions of Shivhei ha-Besht has not yet been fully investigated. Later, Shivhei ha-Besht appeared in many versions, in Hebrew, Yiddish, and Ladino. J. S. Bick records an unpublished translation in Polish in a letter to Mendel Lefin. But even Hasidim had reservations about the work, especially the strange and unreliable stories which aroused the criticism and scorn of the Mitnaggedim and maskilim, who used it as a weapon in their war against Hasidim. It contains some 230 stories, arranged in series united by common themes, heroes, and motifs. Despite its imaginary-legendary character, historical events are recalled along with undoubtedly reliable traditions. Many of the historical events recalled are confirmed in non-hasidic sources.