The Pontifical Council for Promoting Christian Unity is the Roman Curia's office for ecumenism, while the Lutheran World Federation is the largest communion of Lutheran ecclesial communities. In the US, the Lutheran World Federation includes the Evangelical Lutheran Church in America, but neither the Missouri nor Wisconsin Synods.
The common commemoration was opened last year with an ecumenical prayer service between Lutherans and Catholics at the Lutheran cathedral in Lund, Sweden during the Pope's Oct. 31-Nov. 1, 2016 visit.
During the service, Catholics and Lutherans read out five joint ecumenical commitments, including the commitment to always begin from a perspective of unity. Pope Francis and Munib Younan, then-president of the Lutheran World Federation and Lutheran bishop of Jordan and the Holy Land, also signed a joint statement.
Quoting the 2016 declaration between Pope Francis and Younan, this year's statement acknowledged the pain of disunity, particularly that caused by the inability to share in the Eucharist.
"We acknowledge our joint pastoral responsibility to respond to the spiritual thirst and hunger of our people to be one in Christ. We long for this wound in the Body of Christ to be healed. This is the goal of our ecumenical endeavors, which we wish to advance, also by renewing our commitment to theological dialogue," the statement declared.
The new statement also emphasized the commitment to continue this journey toward unity "guided by God's Spirit…according to the will of our Lord Jesus Christ."