I wasn't aware it was evil. It's named after the Enochian language as far as I know. The language itself is said to have been channeled through his friend (a medium) and that it is an Angelic language. So there's the connection for you.

"Dee's journals also refer to this language as "Celestial Speech", "First Language of God-Christ", "Holy Language", or "Language of Angels". He also referred to it as "Adamical" because, according to Dee's angels, it was used by Adam in Paradise to name all things. The term "Enochian" comes from Dee's assertion that the Biblical patriarch Enoch had been the last human (before Dee and Kelley) to know the language. "

As for someone using such "majik" against you (I presume); considering the nature of the system being 'holy' and negative/unjust uses of such would be contrary to the energy, I'd try focusing your defense around an inversion field. Reflect it back.
You can try this with simple mantras regarding returning to sender, return 3 fold, perhaps if you're so inclined ask angelic forces/Christian God to make judgement on it's use against you.

Specifically to Enochinan though:

"Dee believed Enochian to be the Adamic language universally spoken before the confusion of tongues. However, modern analysis shows Enochian to be an English-like constructed language. Word order closely follows English, except for the dearth of articles and prepositions. The very scant evidence of Enochian verb conjugation is likewise reminiscent of English, more so than with Semitic languages such as Hebrew, which Dee said were debased versions of the Enochian language."

So, grain of salt regarding legitimacy of the language; yet, anything can be used to focus intent and build thoughtforms and other structures to affect the tapestry.
I guess with all things, it's important to remember that if you decide to act within the box the other person provides you're playing their game. So regarding this, treat it as any assault on your person and defend as best you know.