In Christian theology, the term Body of Christ has two main but separate meanings: it may refer to Jesus' words over the bread at the Last Supper that "This is my body" in Luke 22:19-20, or to the usage of the term by the Apostle Paul in 1 Corinthians 12:12-14 and Ephesians 4:1-16 to refer to the Christian Church. It may also refer to Christ's post-resurrection body in Heaven.
There are significant differences in how Christians understand the term as used by Christ at the Last Supper and as developed in Christian theology of the Eucharist. For some it may be symbolic, for others it becomes a more literal or mystical understanding.
As used by Saint Paul in the Pauline epistles it refers to the Christian Church as a group of believers. In Roman Catholic theology the use of the phrase "mystical body" distinguishes the mystical body of Christ, the Church, from the physical body of Christ, and from a "moral body" such as any club with a common purpose.
–Wikipedia
