What is a "Chover Chaver"?
Rashi #1, R. Bachya #1 and Targum Yonasan: It is someone who gathers snakes, scorpions or other Chayos 1 to one location.
Rashi #2 (on Yeshayah, 47:9): It is a Lashon of witchcraft.
Ramban: "Chover Chaver ve'Sho'el Ov ve'Yid'oni" are three kinds of sorcerers.
R. Bachye #2: It is someone who gathers Sheidim (demons) to one location.
Sanhedrin, 65a: Irrespective of whether they are large or small - even snakes and scorpions. See Torah Temimah, note 60.
What is the difference between "Ov" and "Yid'oni"?
Rashi (citing Sanhedrin, 65a), R. Bachye and Targum Yonasan: "Ov" is a kind of sorcery that is called 'Pitum', where one raises a dead spirit 1 to under one's armpit (or to between one's joints - Sanhedrin, 65b), from where it speaks; 2 whereas "Yid'oni" places the bone of a Chayah called 'Yado'a' 3 into one's mouth, where it speaks by means of sorcery. 4
See Oznayim la'Torah who elaborates at length.
See R. Bachye - foot of p. 361 - who discusses the Ba'alas Ov of Shaul ha'Melech in detail.
See R. Bachye, p.363.
Ramban: And the Torah writes "Sho'el Ov ve'Yid'oni" to include the client in the Isur - though the Ba'al Ov and Yid'oni himself is subject to Sekilah, and the client, only to a La'av - See Torah Temimah citing Sanhedrin, 65a and note 63 & 64.
What constitutes "Doresh el ha'Meisim"?
Rashi and R. Bachye: It constitutes either raising a dead spirit on his Eiver (male organ), from where it speaks or consulting a human skull (or using any other mechod to consult the dead - R. Bachye).
Sanhedrin, 65b: It constitutes starving oneself before going out to a graveyard so that a Tamei spirit will rest on him. 1
See Torah Temimah, note 65.
