The Sister Catherine Treatise is a work of Medieval Christian mysticism seen as representative of the Heresy of the Free Spirit of the thirteenth and fourteenth centuries in Europe. Wrongly attributed to Christian mystic Meister Eckhart, it nevertheless shows the influence of his ideas or at least the ideas which he was accused or attributed as having had by the Inquisition.

Eckhart von Hochheim, commonly known as Meister Eckhart, Master Eckhart or Eckehart, claimed original name Johannes Eckhart, was a German Catholic theologian, philosopher and mystic, born near Gotha in the Landgraviate of Thuringia in the Holy Roman Empire.