The central theme of the study is Christ as the sacrament of reconciliation of the human being with God. In light of this premise, the study is divided into two main parts. The first part concentrates on the human response to grace, thus personal justification. In this section different but related topics are studied: the human act and its limitations; the nature of sin in antithesis to the virtue of justice implanted in the human heart. The second part of the study takes care of the sacrament of reconciliation as understood in Catholic dogma. An historical survey of the sacrament brings into focus the teaching of the Fathers of the Church which was implemented by ecumenical and particular councils and codifications. The same historical survey prepares the reader for a better understanding of the canons on Penance. The canons of the Latin and of the astern Rite codes are presented with an explanation when necessary. Through the study of these canons it becomes clear that concern of the Church is to protect the sacredness and the dignity of the sacrament as well as the dignity of the penitent.