My brother was a member of the
Churches which follow the New Testament don't use instrumental music. As noted it is because of the absence of authorization for their use in the New Testament. However, your analogy fails to make your point. Musical instruments did exist during the first century. The use of musical instruments was authorized under the Old Testament law (Psalm 150 is an example). It is because the Law of Christ specifically mentions singing (Ephesians 5:19; Colossians 3:16) and does not mention instrumental music in worship which makes us sit up and take notice of this change.