With his excellent skills in ancient Greek and Latin, Dr. Ferguson demonstrated in his book "A Cappella Music in the Public Worship of the Church" that a cappella music was used exclusively in the Jewish Synagogue as part of their rational worship prior to the coming of Christ. In addition, Dr. Ferguson demonstrated that the church described in the New Testament also used a cappella music exclusively in their rational worship. This exclusive use of a cappella music by the church continued for about 1000 years. The church fathers did not simply overlook the use of musical instruments in the public worship of the church. Rather, many of these leaders actively avoided and condemned the use of musical instruments in the public worship of the church. These leaders viewed instrumental music as an inferior way to worship God. Their understanding of "singing and making melody in your hearts to the Lord" (Ephesians 5:19) excluded the use of instrumental music in the public worship of the church. Instrumental music was instituted by the Western (Roman) church in about AD 1000, but this practice was not accepted by the Orthodox Christians in the East. To this day, the vast majority in the Eastern Orthodox Churches use a cappella music exclusively. However, a minority of the Eastern Orthodox Churches in the USA have recently started using instruments. In the West, many of the protestant reformers abandoned the use of musical instruments because they viewed it as a "Catholic corruption." However, the instrument was gradually resumed in most of the protestant churches. This is only a thumbnail sketch of this excellent 140 page book.