Pope Francis's has described his vision for a synodal Church, not simply as a once off programme of renewal, but as God's desire for the Church of the third millennium. As such, it aims to concretise the ecclesiology of the Second Vatican Council, making the Church today more manifestly one of communion, participation, and mission. It differs from previous synods and Councils in history in that it more directly invites and involves all the baptised in a direct process of listening and discernment to the voice of the Holy Spirit. This paper aims to understand from a theological perspective how listening will work in a synodal Church, by exploring firstly what we mean by the ecclesiology of communion from the Council. Such an ecclesiology, manifesting the equal dignity of the faithful in Christ, will ground listening at the level of participation in God as well as acknowledging the gift of infallibility given to the whole Church. It means calling on the Holy Spirit to help discern how and where, the apostolic deposit of faith has been received by members of the body. It also explores what we mean by listening to the sensus fidei of the whole body and how the authority of laity and hierarchy operate both in united but distinct ways within a synodal process grounded in communion ecclesiology. Overall, such listening is to be done carefully for the sake of the Church's mission as the sacrament of salvation to the world.