The UCC was founded in 1957 as the union of several different Christian traditions: from the beginning of its history, it was a church that affirmed the ideal that Christians did not always have to agree to live together in communion. Its motto—"that they may all be one"—is Jesus' prayer for the unity of the church. The UCC is one of the most diverse Christian churches in the United States as it somehow manages to balance congregational autonomy with a strong commitment to unity among its nearly 5,600 congregation - despite wide differences among many local congregations on a variety of issues.

While preserving relevant portions of heritage and history dating back to the 16th century, the UCC and its forebears have proven themselves capable of moving forward, tying faith to social justice and shaping cutting edge theology and service in an ever-changing world. Affirming that Jesus Christ is the Head of the Church, the UCC claims as its own the faith of the historic church expressed in the ancient creeds and reclaimed in the basic insights of the Protestant reformers. Yet the UCC also affirms the responsibility of the church in each generation and community to make faith its own in reality of worship, in honesty of thought and expression, and in purity of heart before God. It looks to the Word of God in the Scriptures, and to the presence and power of the Holy Spirit to prosper its creative and redemptive work in the world.

The UCC recognizes two sacraments: Baptism and the Lord's Supper or Holy Communion.

Hancock Church, Congregational is a member of the Metropolitan Boston Association of the Massachusetts Conference of United Church of Christ.