transubstantiation

Transubstantiation (in Latin, transsubstantiatio) is the change of the substance of bread and wine into the Body and Blood of Christ occurring in the Eucharist according to the teaching of some Christian Churches, including the Roman Catholic Church. In Greek it is called μετουσίωσις.

Theology of transubstantiation

"Substance" here means what something is in itself. (For more on the philosophical concept, see Substance theory.) A hat's shape is not the hat itself, nor is its colour the hat, nor is its size, nor its softness to the touch, nor anything else about it perceptible to the senses. The hat itself (the "substance") has the shape, the colour, the size, the softness and the other appearances, but is distinct from them. While the appearances, which are referred to by the philosophical term accidents, are perceptible to the senses, the substance is not.

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