The aim of this article is to present the paterological elements in the teaching of Benedict XVI. These elements appear as relevant when the Pope discusses other truths of faith. Thus, the papal teaching on God the Father presents Him in nexus mysteriorum of the truths of faith. The article consists of three parts, which correspond to the historical periods in which the truth about God the Father was gradually revealed. The first part discusses the concept of God’s “fatherhood,” which, based on human experience, recognises God as the origin and source of all existence. Additionally, the care and goodness of God towards human beings in the Old Testament proves God’s qualities of a father, and thus the universal brotherhood of all human beings and the necessity of caring for creation as a gift originating in God’s love. The second part of the article reveals the fullness of the revelation about God the Father made in his Son, Jesus Christ. God not only can be called Father, but is indeed Father. The life and teaching of the incarnate Son remained in constant reference to the Father, a fulfilment of his will, and the particular event that revealed this truth to the apostles was the prayer of Jesus. Christology, then, as the Pope makes clear, is the necessary hermeneutical key to paterology. The last part of the article discusses the sanctification of people in baptism. Through this sacrament, people become sons and daughters of the Father in the only-begotten Son and, like Jesus, can address God with the word “Abba.” The mystery of God the Father impels us to discover the other as a brother and to take concrete actions through which, already here on earth, the brotherhood of Christians is made a reality.