This volume presents contributions of the Catholic-Lutheran International Conference held at the Pontifical Athenaeum of St. Anselm in Rome in 2016. The scholars were invited to reflect together on the questions of forgiveness, conversion and penance in the context of the ecumenical dialogue that has been going on since the Second Vatican Council. Precisely because stemming from a deep rethinking of God’s forgiveness, the movement that began half a millennium ago has borne diverse fruits in different traditions. Today, within the context of fraternal dialogue we may be able to recognize in a new way «the signs of God’s mercy». This motivation allows us to discover, in this book, new itineraries and processes of the conversion to God which also leads to the rediscovery and the inauguration of authentic forms of penance, both ecclesial and personal.