In Christian theology, justification is the event or process by which sinners are made or declared to be righteous in the sight of God.

The Joint Declaration on the Doctrine of Justification (JDDJ) is a document created and agreed to by the Catholic Church's Pontifical Council for Promoting Christian Unity (PCPCU) and the Lutheran World Federation in 1999 as a result of Catholic–Lutheran dialogue. It states that the churches now share "a common understanding of our justification by God's grace through faith in Christ." To the parties involved, this essentially resolves the 500-year-old conflict over the nature of justification which was at the root of the Protestant Reformation. The World Methodist Council adopted the Declaration on 18 July 2006. The World Communion of Reformed Churches, adopted the Declaration in 2017.