The written history of the Athame as a magickal tool comes to us from the Lansdowne Manuscript dated 1202 and the Sloane Manuscript dated 1307. Before we go further it must be stated that the manuscripts above were great magickal works and this information was evidently known and practiced well before these manuscripts were written. These are considered to be the only survivors of the book and Witch burnings of the inquisitions. The material contained in these manuscripts is Quabalistic in nature. In the book The Key Of Solomon, L.W. deLaurence's 1914 translation of the manuscripts states that the Black Handled Knife,"...is for making the Circle wherewith to strike terror and fear into the Spirits. It should be made on the day of Mercury, the Hour of Saturn, tempered "thrice" by fire and dipped into the blood of a black cat and juice of hemlock." Likely not something many would want to do with an Athame today.
In Israel Regardie's book, "The Golden Dawn", 1984 the method of "making" the Air Dagger is a very long ceremonial ritual. The Air Dagger is considered to be the equivalent of the Wiccan Athame. This is where so many get confused as to what direction the Athame should correspond to. The Athame my be used as an Air Dagger but it is NOT an Air Dagger. Considering the age of the manuscripts that deLaurence translated and the initial printing of "The Golden Dawn" in 1937 there was a change of attitude as to the Athame, i.e., no more blood used in consecration. Further history shows Greek vases with women commanding Spirits with a short bladed knife. The tool is also represented in sculptural portrayals of Hekate Triformus. "The Clavicle Of Solomon" published 1572, mentions the knife as an "Arthana". Athame may be a subverted form of the word. Additionally Gerald Gardner wrote some lore concerning the Athame in his fictitious work "High Magic's Aid" (first published in 1946) wherein the 3 main characters require one for their magical working and after consulting with a spirit, are told to seek out a witch named Morvan in the countryside who will assist them in their endeavors. For more information on the history of the Athame I would suggest reading "The A.B.C.'s of Witchcraft" by Doreen Valiente.