Vinum Sabbathi/Sabbati translates to Witches' Wine or Wine of the Sabbath.
Most Likely a reference to The Novel of the White powder by Arthur Machen
Men and women, seduced from their homes on specious pretences, were met by beings well qualified to assume, as they did assume, the part of devils, and taken by their guides to some desolate and lonely place, known to the initiate by long tradition, and unknown to all else. Perhaps it was a cave in some bare and windswept hill, perhaps some inmost recess of a great forest, and there the Sabbath was held. There, in the blackest hour of night, the Vinum Sabbati was prepared, and this evil gruel was poured forth and offered to the neophytes, and they partook of an infernal sacrament; sumentes calicem principis inferorum, as an old author well expresses it. And suddenly, each one that had drunk found himself attended by a companion, a share of glamour and unearthly allurement, beckoning him apart, to share in joys more exquisite, more piercing than the thrill of any dream, to the consummation of the marriage of the Sabbath.
It induces a dreamlike trance, almost like a drug trip.
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