This thesis seeks to provide an explication of the ecclesiological significance of the dominical logion from the Gospel of Matthew: Where two or three are gathered in my name, there I am in the midst of them, (Matt. 18:20). The background to the choice of this topic came from the author's interest in the lived experience of the Focolare Movement which has Matthew 18:20 as one of the two main pillars of its spirituality. The motivation behind the choice of title and scope of this thesis comes from the theological writings of Dietrich Bonhoeffer, Avery Dulles and Joseph Ratzinger. They show that within the framework of the ecclesiology of communion, Matt. 18:20 is a fruitful and important biblical text for furthering the Church's progress in the understanding of its own identity and mission as the Community of Jesus' Disciples, called to be the effective and sign-bearing presence of Christ's saving activity. Biblical exegetes, the Fathers of the Church, Vatican II, post-conciliar Magisterial teaching and contemporary theological research all point to the importance of Matt. 18:20 as a key to understanding Matthew's ecclesiology in the context of the increasingly important ecclesiology of communion. Christ's presence in the midst of the community gathered in his name has implications for our understanding of the Church as the community of disciples. The Church is the People of God, gathered as the Body of Christ and the Temple of the Holy Spirit and is called to be a reconciled and reconciling community, existing in and for the world and enlivened by the presence of Emmanuel, God with us.