Yet some, almost in the very same breath, will discount commands to worship with instruments that are given by God in the Old Testament (yet never specifically rescinded in the New) because the OT law which authorized instrumental music has been replaced by the gospel of Christ (which they agree is silent on the matter of instrumental or a cappella-only praise).
So, does the Old Testament have authority or not?
At least a few will ask:
If we can use instrumental music in worship because David did, can we:
1. Offer animal sacrifices? (Psalm 20:3; Psalm 66:13-15)
2. Dance before the Lord (2 Samuel 6:14)
3. Keep the sabbath? (Exodus 20:8)
4. Have many wives? (2 Samuel 5:13)
May I attempt to answer out of my admittedly meager knowledge of scripture and God's nature ...
1. No. Well, you could, but it'd be pointless. And there'd be no temple at which to do it. (Hebrews 10:3-10).
2. Maybe. Never specifically rescinded or revoked in the New Testament. Why do you ask? Do you not like dancing? Or just not feel like dancing when you suddenly, more fully perceive the grace and providence and love of God?
3. Maybe. Never specifically rescinded or revoked in the New Testament. (But see Mark 2:23-28.) Is the Son of Man no longer Lord of the Sabbath? Would it be a bad thing to keep the Sabbath and rest as God rested on the seventh day, the day before our work for him begins again on Sunday?
4. No. (Ephesians 5:31; Mark 10:5-9).
And, when confronted with the presence of harps in the highly-symbolic Revelation to John, a few will ask questions like these:
1. Why should we believe that these are literal harps in a highly symbolic book like Revelation? (Revelation 5:8; 14:1-2; 15:1-3)
2. If the golden bowls full of incense are a symbol for the prayers of the saints, why wouldn’t the harps be a symbol for the praise of the saints? (Revelation 5:8)
3. If the harps in heaven authorize instrumental music in worship here on earth, do the golden bowls full of incense authorize the burning of incense in worship here on earth? If not why not? (Revelation 5:8)
4. Did John hear a harp or a voice? (Rev. 14:1-2, ASV)
5. Since all the victorious had harps, shouldn’t every Christian play a harp in worship today? If not why not? (15:1-3)
6. If harps are authorized by these passages, why do most churches use nearly everything but harps?
7. If these passages authorize instrumental music in worship here on earth, why didn’t the early church have instrumental music?
8. Even if there really are harps in heaven, does this prove that God wants instrumental music in worship here on earth (cf. Matthew 22:30; Hebrews 4:14 & 8:4; Revelation 7:16-17.)
Again, if I may be forgiven a pauper's intellect with regard to scripture and the will of God:
1. Why should you not believe that these are literal harps in a highly prophetic book like Revelation?
2. Well, possibly the harp each held is a symbol for the prayers of the saints, as well as the bowls of incense they all held. Isn't the word for "harp" plural there? Making it pretty hard to play more than one and hold more than one bowls or vials and sing, which they did in the next verse. But at least the four living creatures or beasts had six wings each, which may have helped. I don't know about the elders. Are you saying that all Christians are symbolized by these beasts and elders? Where do you get that?
3. You really are hung up on that "authorize" stuff, aren't you? You see, I never insisted that this scripture authorized the use of instruments on earth. I would merely point out that God chose these symbols to describe worship with instruments to Him in heaven, and commanded them in the Old Testament and never revoked the command in the New. Do you have something against incense? If a church chose to burn incense as described here in an attempt to help its members picture the wonder of heaven and its glorious worship, would that be a sin?
4. In the American Standard Version you specify, John hears "a voice as of the voice of harpers." In the KJV, it is "the voice of harpers harping with their harps." In the NIV, he hears a "sound ... like that of harpists playing their harps," which is virtually the same wording as the New KJV, Young's Literal, and the NASV. Happy? Can we nitpick something else irrelevant but different now?
5. If we are all commanded to have harps by this example, then shouldn't we sing only the song of Moses and the Lamb, since it is the only song authorized? Does anyone have the sheet music to that one? Anyone? Bueller? Bueller?
6. Why do most churches use everything but harps in their instrumental praise? Man, have you priced one of those hummers? And they're huge and heavy these days, too! It's hard to find little ones you can carry in one hand while balancing a bowl in the other. Let alone getting more than one for each member, just to be in compliance with Revelation 5:8 as you suggest! Of course, some of those churches might also be going back to Psalm 150 for their authorization, and coming as close as they can. Or maybe they're not sold on the notion that everything they do in worship must be specifically, letter-for-letter authorized because they don't find that to be a guiding principle of the New Covenant. Maybe they find it ridiculous that God would accept a harp but reject a guitar because He didn't prophetically authorize it in scripture. I don't know, really. You'd have to ask them.
7. Ah, that assumes that the early church didn't have instrumental praise. Ever, one would suppose from the way you pose the question. Even when the church early on in Acts met daily in the temple, where instrumental worship was commanded by God (2 Chronicles 29:5). Can you show me where in scripture it says that the church didn't celebrate with instrumental praise? (No, I'm not talking about quoting a bevy of scholars and historians who agree with you and confidently assert it; I mean proof. - Would you accept the word of scholars and historians I could quote who disagree? No? You can't say it is a fact if there isn't proof.) Can you do that? Or otherwise prove this negative?
8. Even if there really are harps in heaven, does this prove that God wants instrumental music in worship here on earth, you ask? I dunno. If there were not harps in heaven, would it prove that He doesn't? What did Jesus pray in Matthew 6:10? Or does it make more sense to conclude that since God doesn't specify a preference in scripture after the arrival of His Son on earth, that we shouldn't, either?
Sorry; I hope that doesn't sound disrespectful, but you've got to at least recognize that I find us (as a fellowship of believers) teetering on the very edge of absurdity in even bringing up some of these arguments and questions about something as serious (and yet ecstatic and heart-clutching and mind-riveting) as our worship together. Some would say we done fell off long ago.
That's why, along with my confessedly manifest ignorance, I am not going to go ahead with a discussion of psallo, and psalleto or any number of other words which would have us throwing quotes from disagreeing linguists at each other. A good, solid knowledge of Biblical languages can often be helpful in determining the meaning of words. But arguments over words don't prove anything. Words change in meaning over time; pretty much everyone accepts that. And some meanings remain intact with their original words for-nearly-ever. Which is it for these words? You don't know and I don't know. I find the guiding principle here is 2 Timothy 2:23.
So I return to my original question: With regard to the authority of scripture as God's binding word and authority forever, can you have it both ways with the Old Testament? It is, but it isn't? And who determines where it is and where it isn't?
Or is there something consistent about God's nature as revealed in all of scripture that transcends our concepts of old and new, justice and mercy, "precept and promise, law and love combining 'til night shall vanish in eternal day?"
Is He unclear about any of it that we absolutely need to know?
Does He leave crucial parts of it out?
Does He require us to assume and presume and build intricate structures of syllogism and deduction and proof and principle and law where He has not spoken?
Or does He ask us to believe a simple, perfect, incarnate Truth ... and then cherish our praise and gratitude to Him for that Truth, however imperfect our worship may be?