Communion

Fellowship with God (Gen. 18:17-33; Ex. 33:9-11; Num. 12:7, 8), between Christ and his people (John 14:23), by the Spirit (2 Cor. 13:14; Phil. 2:1), of believers with one another (Eph. 4:1-6). The Lord's Supper is so called (1 Cor. 10:16, 17), because in it there is fellowship between Christ and his disciples, and of the disciples with one another.

in a religious sense, refers chiefly to the admission of persons to the Lord’s Supper. This is said to be open, when all are admitted who apply, as in the Church of England; to be strict, when confined to the members of a single society, or, at least, to members of the same denomination;