At the core of the Christian faith is the realization that at the peak moment of the Mass, the Holy Bread becomes the flesh of Jesus and the wine, his blood. The belief in transsubstantiatio, the change of essence, is one example of the complex relationship of Christian culture to matter. This course will deal with various aspects of matter and materiality in the Middle Ages. We will examine different materials, their symbolism, their value and the way they were used to convey theological or other ideas. We will distinguish between the meaning of natural materials, stone wood and water compared to processed materials, such as textiles and materials derived from the body of saints such as tears, bone, and blood. We will deal with the changing material, the material that stimulates miracles, the meaning of the intrinsic touch with matter as well as the observation of certain materials. We will examine changes in materials and changes in the encounter between matter and its environment. Particular attention will be devoted to examining how certain materials were sanctified and how the transfer of matter, such as soil, water, or oil, could transfer the sanctity of a holy place.