Does worship in the Hebrew Bible include musical instruments? Check. These mainly include membranophones like various hand drums and tambourines (e.g., Exod 15:20-21), idiophones like cymbals and bells (e.g., 2 Sam 6:5; 1 Chron 15:16; Exod 28:33-34), chordophones like lyres and harps (e.g., Ps 68:25; 81:2; 149:3; 2 Chron 20:28), and aerophones like various kinds of reed-pipes/flutes, horns, and trumpets (e.g., Isa 30:9; 1 Kings 1:40; 1 Chron 15:28; 2 Chron 5:12-13). Instruments are a major part of the worship of God in the Hebrew Bible.
Psalm 150, the last Psalm positioned as the response to the entire book of worship commands with multiple imperatives,
"Praise the LORD!
Praise God in His sanctuary;
Praise Him in His mighty expanse.
Praise Him for His mighty deeds;
Praise Him according to His excellent greatness.
Praise Him with trumpet sound;
Praise Him with harp and lyre.
Praise Him with timbrel and dancing;
Praise Him with stringed instruments and pipe.
Praise Him with loud cymbals;
Praise Him with resounding cymbals.
Let everything that has breath praise the LORD.
Praise the LORD!"
The congregation assembled to see the ark brought up and worshiped God as follows:
"So all Israel brought up the ark of the covenant of the Lord with shouting, to the sound of the horn, atrumpets, and cymbals, and made loud music on bharps and lyres" (1 Chron 15:28; also see 13:8).
"When the priests came forth from the holy place (for all the priests who were present had sanctified themselves, without regard to divisions), and all the Levitical singers, Asaph, Heman, Jeduthun, and their sons and kinsmen, clothed in fine linen, with cymbals, harps and lyres, standing east of the altar, and with them one hundred and twenty priests blowing trumpets in unison when the trumpeters and the singers were to make themselves heard with one voice to praise and to glorify the LORD, and when they lifted up their voice accompanied by trumpets and cymbals and instruments of music, and when they praised the LORD saying, “He indeed is good for His lovingkindness is everlasting,” then the house, the house of the LORD, was filled with a cloud, so that the priests could not stand to minister because of the cloud, for the glory of the LORD filled the house of God (1 Chron 5:11-14).
The theology of worship given to us in the Hebrew Bible is that when the congregation is in the presence of God, which is what the ark represents, singing and instruments (and dancing) are used in the celebration of His presence.
Are instruments used by the angels and God's people in heaven? Check.
In worship of the Lord Jesus Christ in heaven, the angels and men worship Him with instruments.
"And I saw between the throne (with the four living creatures) and the elders a Lamb standing, as if slain, having seven horns and seven eyes, which are the seven Spirits of God, sent out into all the earth. And He came and took the book out of the right hand of Him who sat on the throne. When He had taken the book, the four living creatures and the twenty-four elders fell down before the Lamb, each one holding a harp and golden bowls full of incense, which are the prayers of the saints. And they sang a new song, saying, “Worthy are You to take the book and to break its seals; for You were slain, and purchased for God with Your blood men from every tribe and tongue and people and nation. “You have made them to be a kingdom and priests to our God; and they will reign upon the earth.” (Rev 5:6-10)
Notice that they sung to Him a new song, not a Psalm either.
So, in both the Old Testament and in the New Testament depiction of heaven, those who are assembled in God's presence respond to His presence in the joy of music, using psalms, hymns, and spiritual songs, old and new, with all sorts of instruments made of metal, wood, animal hides, stringed and unstringed.
So why do some make the argument that the church when assembled in God's presence should not use them?
I would argue it is due to Gnostic assumptions. The first Gnostic assumption is that of the principle described in the NT as "do not taste, do not touch." Colossians 2:21 speaks of these teachers as those who strictly deny the use of certain objects in worship because they are considered worldly. Certain foods, certain items in the world that would be considered unclean, are forbidden by the Gnostic ascetics because what is spiritual should not incorporate that which is physically viewed as defiled.
Some make the argument that because instruments were made by wicked men and used in the worship of their pagan worship, these instruments should not be incorporated into the worship of God.
They argue that this is confirmed from the fact that the New Testament never speaks of musical instruments being used in worship services.
This brings me to the second Gnostic assumption: the argument for a radical discontinuity between the Old and New Testament. The New Testament actually doesn't describe a first century church service in detail at all. It just describes the essential components of a church assembly (i.e., the teaching of the Word/the apostles, the fellowship of the saints, and the taking care of the poor). We're never told of how the church is conducted beyond this because we already have sufficient pictures of worship in the Old Testament. I liken this to morality. We don't have any new morality given to us in the New Testament. It simply emphasizes that the morality that we are taught in the Old Testament needs to be thought of within the framework of love of God and neighbor and applied in a more consistent manner than was tolerated by God in the Old Testament. But the moral principles are the same. I would argue that the pictures of worship we are given in the Old Testament communicate principles that are also the same. One of those principles is that every created thing can be used to worship God because all of creation should worship God and this includes forming created things into instruments for use in the worship of God by his assembly.
But the Gnostic tendency is to see creation as corrupt and therefore only the created things that God tolerates can be used to worship Him. Everything else is too unclean to use in the presence of God and this is proven by the fact that pagans use them in their false worship. Instruments are worldly. Voices are invisible. Voices are spirit and therefore spiritual. Hence, only voices should be used.
I'm sure those who argue this way would not like the Gnostic label applied to them but this appeal to the regulative principle is misguided. The regulative principle has to do with not just what is explicitly referenced within the New Testament but rather what is explicitly and by good and necessary consequence referenced in the entire Bible as fit for the assembly to use in worship of God in His presence.
Hence, arguing that musical instruments get in the way of worship and that the New Testament tells us to use our voices, and this somehow means that we are only to use our voices, is negated by the use of instruments both throughout biblical worship here on earth and in heaven. All other pragmatic arguments should give way to the fact that we are commanded in the Psalms, the Word of God, to use instruments in our praise of God.