Ecclesia Dei is the document Pope John Paul II issued on 2 July 1988 in reaction to the Ecône consecrations, in which four priests of the Society of Saint Pius X were ordained as bishops despite an express prohibition by the Holy See.

John Paul called for unity and established the Pontifical Commission Ecclesia Dei to foster a dialogue with those associated with the consecrations who hoped to maintain both loyalty to the papacy and their attachment to traditional liturgical forms.

Referring to these consecrations, the Pope wrote in Ecclesia Dei: "In itself, this act was one of disobedience to the Roman Pontiff in a very grave matter and of supreme importance for the unity of the Church, such as is the ordination of bishops whereby the apostolic succession is sacramentally perpetuated.

[5] The Pope instituted the Pontifical Commission Ecclesia Dei to assist those who had been associated with Archbishop Lefebvre but who wished "to remain united to the Successor of Peter in the Catholic Church, while preserving their spiritual and liturgical traditions, in the light of the Protocol signed on 5 May last by Cardinal Ratzinger and Mons.

The Pope stated: "Respect must everywhere be shown for the feelings of all those who are attached to the Latin liturgical tradition, by a wide and generous application of the directives already issued some time ago by the Apostolic See for the use of the Roman Missal according to the typical edition of 1962".

On 8 July 2009, in Ecclesiae unitatem, he modified its position within the Roman Curia by making the Prefect of the Congregation for the Doctrine of the Faith (CDF) the ex officio head of the Commission.