The term brothersister is used with multiple meanings in the Greco-Roman world: compatriot, friend, colleague, every man especially in Stoicism; furthermore, it assumes a religious meaning as coreligionist already in the Greek confraternities and in the mystery religions; later in the NT, especially in the Synoptics, the Acts of the Apostles and in the Pauline letters, it designates every member of the Christian community. The expression brothersister expresses several ideas at the same time. First, it expresses the suppression of every differentiation of race, age, condition and sex. Second, it expresses the new bonds, stronger than those of blood, created by the spiritual unity of those who fulfill the will of God see Mk 3:35. And third, it expresses the common baptism, which renders the Christian, on the one hand, a child of the heavenly Father and, on the other, a brothersister in the faith to every member of the Christian community, coheir of the same hope, ready to recognize in every person the image of God. The term continued in the first Christian writers to indicate the faithful Clement of Rome, Didache, the Apologists; even Lucian, in Mort. Peregr. 13, makes use of it to indicate the Christians; Justin in Apol. 1,65 writes that the neophyte is led to the brethren. At the same time, with baptism Christians have a more vivid awareness of the universal brotherhood Ignatius, Eph. 10,3; Justin, Dial. 96,2; Aristides, Apol. 15,6; Clement Al., Strom. 7,14,85; Tertullian, Apol. 39,8. The term is deepened christologically: Christ, who has become our brother and the firstborn, leads us to God the Father and makes us participants in the fraternity of a new birth Origen, Orat. 15,4; Athanasius, Or. c. Arian 2,62; Gregory of Nyssa, Ref. conf. Eun. 80-82; Contra Eun. 3,10,1. The pagans, interpreting such terms viciously, accused the Christians of sexual promiscuity and incestuous unions, accusations amply refuted by the Apologists Athenagoras, Leg. 32,4-5; Theophilus Ant., Ad Aut. 3,13; Minucius, Octav. 9 and 31.
BROTHERSISTER Gallery Photos