Hi Disillusioned, my post on Psalm 110 was intended for Gman.
I agree with you that the NT authors took a meaning from Psalm 110 that was different from what the author originally intended. But I don’t know that means the interpretation is not valid. The Bible itself contains the idea that authors sometimes do not fully understand what they are writing. And it’s not so much that Christians tend to deny the original meaning of a text, but that they add another meaning on top. For example, I’m pretty sure the original Christians realised that when God ‘called his son out of Egypt’ in Hosea 11:1, it meant the nation of Israel. When Matthew applied this verse to Jesus I tend to think that he was not denying the original meaning of the verse but that he was adding a prophetic significance and applying it to Jesus. The NT makes such typologies explicit when Hebrews says Jesus is the greater Melchizedek, when Jesus talks about the ‘sign of Jonah’, and when Paul says that Jesus is the rock that the Israelites followed in the desert. It is true that Acts 2 apparently argues against applying Psalm 110 to David, but even here, I suspect, what the author means is ‘not only to David’ and picks out a clue that a more appropriate application of the text can be made to Jesus.
As for the matter of ruling among enemies, I don’t know. There are lots of possible ways of understanding this if the current JW interpretation is wrong. For example, during the millennium there will continue to be unbelievers, culminating in the rebellion at the end of the thousand years. Jesus could be said to be ruling among his enemies at this time and they are only finally put under his feat at the end, as indicated in 1 Corinthians 15.