thumb|[[Revelation 5:8 presents the saints in Heaven as linked by prayer with their fellow Christians on earth]]
The communion of saints (Latin: , ), when referred to persons, is the spiritual union of the members of the Christian Church, living and the dead, but excluding the damned. They are all part of a single "mystical body", with Christ as the head, in which each member contributes to the good of all and shares in the welfare of all.
The earliest known use of this term to refer to the belief in a mystical bond uniting both the living and the dead in a confirmed hope and love is by Saint Nicetas of Remesiana (); the term has since then played a central role in formulations of the Christian creed. Belief in the communion of saints is affirmed in the Apostles' Creed.
The word sanctorum in the phrase can also be understood as referring not to holy persons, but to holy things, namely the blessings that the holy persons share with each other, including their faith, the sacraments and the other spiritual graces and gifts they have as Christians.
History
The concept of the communion of saints is linked with Paul's teaching, as in Romans 12:4–13 and 1 Corinthians 12:12–27, that in Christ Christians form a single body.
The New Testament word (, 'saint') can refer to Christians who, whatever their personal sanctity as individuals, are called holy because they are consecrated to God and Christ. This usage of the word saint is found some fifty times in the New Testament.
The Heidelberg Catechism, citing Romans 8:32, 1 Corinthians 6:17, and 1 John 1:3, asserts that all members of Christ have communion with him, and are recipients of all his gifts. Similarly, the Catechism of the Catholic Church states: Since all the faithful form one body, the good of each is communicated to the others.... We must therefore believe that there exists a communion of goods in the Church. But the most important member is Christ, since he is the head.... Therefore, the riches of Christ are communicated to all the members, through the sacraments.' 'As this Church is governed by one and the same Spirit, all the goods she has received necessarily become a common fund.
The persons who are linked in this communion include those who have died and whom Hebrews 12:1 pictures as a cloud of witnesses encompassing Christians on earth. In the same chapter, Hebrews 12:22–23 says Christians on earth "have come to Mount Zion, and to the city of the living God, the heavenly Jerusalem, and to innumerable angels in festal gathering, and to the assembly of the firstborn who are enrolled in Heaven, and to a judge who is God of all, and to the spirits of just men made perfect."
Western Christianity
Roman Catholicism
In Roman Catholic terminology, the communion of saints exists in the three states of the Church, the Churches Militant, Penitent, and Triumphant. The Church Militant () consisting of those alive on earth; the Church Penitent () consisting of those undergoing purification in purgatory in preparation for Heaven; and the Church Triumphant () consisting of those already in Heaven. The damned are not a part of the communion of saints. Roman Catholics ask the intercession of saints in Heaven, whose prayers are seen as helping their fellow Christians on earth (Revelation 5:8).
According to the Catechism of the Catholic Church:
Lutheranism
Martin Luther defined the phrase thus:
Lutheranism affirms that the Church Militant (those alive on earth) and Church Triumphant (those alive in heaven) share a common goal and thus do pray for one another. The Augsburg Confession affirms that the saints "pray for the Church universal" in life and in heaven. The Apology of the Augsburg Confession teaches that the "blessed virgin Mary prays for the Church". In this way, Evangelical Lutheranism accepts a form of the doctrine of the intercession of the saints (while it rejects the invocation of the saints). The Book of Concord, the official compendium of Lutheran doctrine, teaches:
"... we know that the ancients speak of prayer for the dead, which we do not prohibit; but we disapprove of the application ex opere operato of the Lord's Supper on behalf of the dead." By the expression , it is meant the belief that the performance of the rite would of itself benefit the dead. The largest Lutheran denomination in the United States, the Evangelical Lutheran Church in America, "remembers the faithful departed in the Prayers of the People every Sunday, including those who have recently died and those commemorated on the church calendar of saints". In Funeral rites of the Evangelical Lutheran Church, "deceased are prayed for" using "commendations: 'keep our sister/brother ... in the company of all your saints. And at the last ... raise her/him up to share with all the faithful the endless joy and peace won through the glorious resurrection of Christ our Lord.'"
Anglican Communion
The Anglican Communion holds that baptized Christians "are 'knit together' with them 'in one communion and fellowship in the mystical body of [Christ]'." The Church of Ireland teaches that:
Methodism
In Methodist theology, the communion of saints refers to the Church Militant and Church Triumphant. The Rev. Katie Shockley explains the communion of saints in the context of the Methodist sacrament of the Eucharist: