Some, not many, church groups do not believe in the use of musical instruments in public worship. The major example is the Churches of Christ. No less than one of their foremost scholars, Everett Ferguson, takes up his case agains the use of instruments in public worship (The Early Church and Today, vol. 1). What are the arguments against the use of instruments?
First, Christians sang in public worship already in the apostolic era: 1 Cor 14:15, 26; Hebrews 2:12; Eph 5:19; Col 3:16. In these contexts no one mentions any instruments. Silence doesn’t prove the case, but it is part of the case. No text prohibits instruments.
Second, the Greek work psallo, “to psalm” or “to make melody,” could be used for using stringed instruments but Ferguson argues this term was often used among Jews for non-instrumental “rendition of their religious songs” (278). The term us used in the NT close to terms for singing or praying. So he suggests the term in the NT is used for vocal and not instrumental music.
Third, Christian history. Again, as in the NT, there is singing but no mention of instruments in public worship. Indeed, some observed the absence of instruments in Christian worship. Eusebius: “We render our hymn with a living psalterion… more acceptable than any musical instrument.” Ferguson sees this as “particularly strong” (280).
Fifth, the Christian assembly. He argues from the importance of edification to the need for vocal music but not instruments since edification is instruction. In find this argument simply flawed, and it ought to be dropped. Some people can be edified by instruments, simple fact.
Sixth, the argument from the nature of human service to God. God is spirit and worship is to be non-material. Spirituality is the focus. This argument, too, ought to be dropped… instruments can effectual spirituality. For many instruments, like a violin, do just that.
Apart from five and six, the other arguments are reasonable though I think number four has a weakness. In the end, argument from the NT is by way of silence and silence is not compelling to me. The text from Eusebius, in my view, is substantive and worthy of consideration.