Theology · Our Lady

Why Did Pius XII Define the Assumption, and How Can a Dogma Not Be in the Bible?

The Hardest Question

The doctrine itself is straightforward: at the end of her earthly life, Mary was taken up body and soul into heavenly glory. (For the basic explanation, see What Is the Assumption of Mary?)

The theological question is harder. The New Testament does not describe Mary’s death or Assumption. There are no first-century accounts. The earliest narratives of her “falling asleep” come from the late fifth century, and they are apocryphal texts mixed with legend.

Yet in 1950, Pope Pius XII solemnly defined the Assumption as a dogma “divinely revealed.” How can the Church say that God revealed something that is not in the Bible and is not attested by historical witnesses?

The answer says a great deal about how the Church understands revelation itself.

What the Church Did Not Claim

It helps to be clear about what Pius XII did not do.

He did not rest the dogma on the apocryphal stories. The Transitus Mariae texts and their colourful details (the apostles gathered from the ends of the earth, the empty tomb discovered by Thomas) played no role in the definition.

Nor did he claim to have found a historical document proving the event. The Church does not define doctrines by discovering new evidence. Public revelation ended with the apostles (CCC 66).

Tradition Is Not a Second Bible

Catholics hold that God’s revelation is handed on through both Sacred Scripture and Sacred Tradition (CCC 80–83). But Tradition is not a secret store of extra facts passed down by word of mouth. It is the living transmission of the whole faith of the Church: her worship, her teaching, her understanding of Scripture, guided by the Holy Spirit.

A truth can be contained in that deposit implicitly: present in what was revealed, but not yet spelled out. Over time, as the Church reflects and prays, it comes into clearer focus. This is what Catholics mean by the development of doctrine.

The clearest comparison is the canon of Scripture itself. No book of the Bible lists which books belong in the Bible. The Church recognised the canon by her faith, through Tradition. A Christian who accepts the New Testament already accepts that some revealed truths are known through the Church’s Tradition rather than stated in a biblical text.

How the Belief Grew

The Assumption appears in the Church’s life before it appears in her theology.

By the sixth century, a feast of the Dormition, the “falling asleep” of the Mother of God, was kept in Jerusalem and across the East. Around the year 600, the Byzantine Emperor Maurice fixed it on 15 August throughout the empire. Rome adopted the feast in the seventh century.

In the eighth century, great Eastern preachers such as St John Damascene and St Germanus of Constantinople preached on it, explaining why it was fitting that the body which bore God should not see corruption. Over the following centuries the belief became universal in both East and West. No Church ever claimed relics of Mary’s body, though relics of lesser saints were eagerly sought.

By the time of the definition, the Assumption had been celebrated by the whole Church for well over a thousand years.

The Consultation

In 1946, Pius XII sent a letter, Deiparae Virginis Mariae, to every Catholic bishop in the world. He asked two questions: did they judge that the Assumption could be defined as a dogma, and did they and their people desire it?

The answer was almost unanimous. Of more than a thousand bishops, the overwhelming majority said yes.

This mattered because the Church teaches that the whole body of the faithful, anointed by the Holy Spirit, cannot err in matters of belief when it shows universal agreement in faith and morals (Lumen Gentium 12; CCC 92). This “sense of the faith” (sensus fidei) is not a poll. It is the Spirit’s witness in the whole Church. When the bishops in union with the Pope, and the faithful with them, are at one in holding a truth as part of the faith, that agreement is itself a sign that it belongs to revelation.

The Theological Reasons

In Munificentissimus Deus, the apostolic constitution of 1 November 1950, Pius XII set out the reasons that show the Assumption to be part of the faith. They are not proofs in the sense of a historical demonstration. They are connections with other revealed truths.

Mary’s union with Christ. Mary was united with her Son in His whole saving work, from the Incarnation to the Cross. It is fitting that she should share in His victory over death.

The Immaculate Conception. Bodily corruption is a consequence of sin. Mary, preserved from all sin, was fittingly preserved from corruption too.

The divine motherhood. Christ honoured His mother. It is hard to imagine Him leaving the body from which He took His own flesh to decay in the grave.

The new Eve. The Fathers saw Mary as the new Eve beside Christ, the new Adam, in the struggle against the serpent (Genesis 3:15). St Paul teaches that Christ’s victory is completed in the defeat of death (1 Corinthians 15:54–57). The new Eve shares that victory fully.

Scripture does not narrate the Assumption, but Pius XII presented it as the fulfilment of what Scripture teaches about Mary and about the resurrection.

Did Mary Die First?

The definition carefully says that Mary was assumed “having completed the course of her earthly life.” Pius XII left open whether she died.

Two views have been held. The great majority of the tradition, especially in the East, holds that Mary died and was then raised: hence the name Dormition. A minority of theologians, sometimes called “immortalists,” argued that since death is a penalty of sin, the sinless Mary did not die. St John Paul II, in a general audience in 1997, said that the more likely view is that she shared in her Son’s death before sharing in His Resurrection.

The Orthodox Perspective

The Orthodox Churches celebrate the Dormition and believe that Mary was taken bodily into heaven. Their objection is not to the belief but to the act of defining it as a dogma by papal authority. This is part of the wider question of the Pope’s role, not a disagreement about Mary herself.

What the Definition Shows

The Assumption is a test case for how Catholics understand revelation. If Christian truth were limited to what can be proved from a biblical text, the Assumption could not be a dogma. But the Church has never worked that way. She reads Scripture as a whole, in the light of the living faith that produced it, under the guidance of the Spirit whom Christ promised would lead her into all truth (John 16:13).

The Assumption also points to our own future. Mary’s bodily glory is what every faithful Christian awaits at the resurrection. Many have noted the timing: the definition came five years after a world war that had treated human bodies with appalling contempt, and it proclaimed instead the dignity of the body and its destiny in God.