Kommentar zu Dewarim 18:11

וחבר חבר OR A CHARMER — One who charms snakes or scorpions or other creatures into one spot (חבר = “an assembly”) (Sifrei Devarim 172:1).

וחובר חבר, the tone-sign is on the letter ח just as it is in the word חרב, cherev, both in Jeremiah 21,2 and in Samuel II 11,25, this is proven by the plural mode in Psalms 56,8 being חברים, chavarim, with the emphasis on the letter ר just as in melech- melachim, and the vowel kametz, instead of tzeyreh.. If the emphasis were on the letter ב, i.e. on the last syllable as in חבר, (friend) in Psalms 119,63 Genesis 32,26 ירך as well as in the words גדר, gader in Numbers 22,24 where the emphasis is on the letter ד, then the plural mode would not have the vowel kametz under the second consonant in Psalms 56,8 but would have the vowel tzeyreh.

Someone who conjures up [the dead] onto his male organ. I.e. he conjures up the dead onto his male organ and it speaks there.