In the Bible, the term "brethren" is derived from the Greek word "adelphoi" (ἀδελφοί) in the New Testament, and the Hebrew word "achim" (אֲחִים) in the Old Testament. Generally, "brethren" signifies a close familial relationship, primarily denoting brothers or siblings. However, its usage extends beyond biological relationships to encompass a broader community of faith. In the early Christian context, "brethren" was often employed to refer to fellow believers, emphasizing unity and shared identity in Christ. For instance, in Acts 1:15, the disciples are described as gathering together and referring to one another as "brethren," highlighting their communal bond in the wake of Jesus' resurrection.Furthermore, the term carries theological significance, reflecting the concept of spiritual kinship among believers. Paul frequently uses "brethren" in his epistles to address members of the church, encouraging them to act in love and unity (e.g., Romans 12:1, Galatians 6:1). This sense of brotherhood underscores the idea that all believers are part of one spiritual family, united under God’s fatherhood (Ephesians 2:19). Therefore, "brethren" encapsulates both the relational and communal aspects of Christian life, calling believers to embody love and support within the body of Christ.