The terms obeah and wanga are African diasporic words that occur in The Book of the Law (the sacred text of Thelema, written by English author and occultist Aleister Crowley in 1904): Also the mantras and spells; the obeah and the wanga; the work of the wand and the work of the sword; these he shall learn and teach.
[3] Richard Allsopp mentions that Bell equates wanga with obeah, and further notes that it is more commonly spelled ouanga in Haiti.
[4] Gordon Rohlehr notes that the word wanga refers to the "obeahman's power to cast spells and the much-feared sexuality of the old woman which could 'blight' a young man.
"[5] In his Commentaries, Crowley explains: The obeah is the magick of the Secret Light with special reference to acts; the wanga is the verbal or mental correspondence of the same.
[...] The "obeah" being the acts, and the "wanga" the words, proper to Magick, the two cover the whole world of external expression.