Westminster Larger Catechism

The Lord's supper is a sacrament of the New Testament,¹⁰⁷⁷ wherein, by giving and receiving bread and wine according to the appointment of Jesus Christ, his death is showed forth; and they that worthily communicate feed upon his body and blood, to their spiritual nourishment and growth in grace;¹⁰⁷⁸ have their union and communion with him confirmed;¹⁰⁷⁹ testify and renew their thankfulness,¹⁰⁸⁰ and engagement to God,¹⁰⁸¹ and their mutual love and fellowship each with the other, as members of the same mystical body.¹⁰⁸²