The answer
Our Coptic Church is in communion with the Ethiopian church because it believes in the same dogmas. It is true that the Ethiopian Church adopted some extra books and added them to the Holy Bible as canonical. Our Coptic Orthodox Church does not accept these books as inspired by God, but the church accepts some of them as authentic writings and teachings of the early fathers.The Book 'The Shepherd of Hermas' is actually taught as Early Church Writings in the Patrology courses, in the Coptic School of Theology.
Answered by His Eminence Metropolitan Youssef (opens in a new tab)