The Lord said to my Lord

I saw a video clip by unitarian apologist Anthony Buzzard: 

https://www.youtube.com/watch?v=GrQQZcQkdes

He says Jews very carefully distinguish between the Lord God (i.e. Adonai, divine name, alternative for Yahweh) and human lords (i.e. Adoni, non-deity lord).

This raises a raft of issues:

1. Unitarians like Buzzard grant that Ps 110 is a Davidic psalm and a messianic psalm. So I can take that for granted in my post.

2. His argument in v1 relies on the MT. There's nothing necessarily wrong with that. However, the vowel points are editorial additions. So we need to distinguish between the original consonantal text and the MT. In both v1 and v5, the same root word is used. 

If, moreover, the MT is reliable in v1, then it's reliable in v5. 

3. Buzzard commits a common semantic fallacy by failing to distinguish between sense and reference. Even if Adoni generally refers to human masters, it doesn't mean human master. It simply denotes someone in authority over another or others. 

4. The term is used in Josh 5:14 and Judg 6:13 for the Angel of the Lord. In context, that's arguably a theophany. So it can be applied to the Deity.

5. The fact that a human or neutral descriptor is used does not imply that the individual so designated is not the Deity. The Bible uses human or neutral descriptors for Yahweh. It describes Yahweh a husband, father, potter, farmer, and shepherd. Those aren't divine descriptors. To the contrary, they are customarily and primarily human descriptors. They derive their meaning from their use in human roles and occupations. 

There's a logical difference between:

i) Not saying X is the case 

and

ii) Saying X is not the case

If v1 refrains from saying the messiah is deity, that's not equivalent to saying the messiah is not deity. It just means v1 doesn't speak to the question of his deity one way or the other.

6. In v5, Adonai is used, which Buzzard himself says is an alternate divine name for Yahweh. Who's the referent of Adonai in v5? The messiah, or Yahweh is distinction to the messiah? On the face of it, there are multiple reasons to think v5 designates messiah as Adonai:

i) There's the parallel between v1 and v5. Both passages use the righthand imagery, and both passages use the same root word. So it's logical to construe their interrelationship this way:

v1: Yahweh's oracle to my [David's] master [i.e. messiah]: Sit at my right hand

v5 Adonai [i.e. messiah] by your [i.e. Yahweh's] right hand

ii) In addition, that would preserve a consistent subject throughout the psalm. In vv2-4, messiah is the military conquer. Messiah is evidently the military conqueror in v7. And there's no textual clue that the subject changes from v6 to v7. 

To say that Adonai in v5 refers to Yahweh in v1 rather than messiah represents an abrupt shift. That interrupts the flow of thought, the corollary metaphor (to the right of), and the same root word. 

7. Whether Ps 110 predicts a divine messiah doesn't solely turn on who Adonai is in v5, but on the threefold comparison and contrast between Yahweh, David, and messiah. There's only so much metaphysical furniture in the OT worldview. You have God, angels, humans, and the subhuman order. In what sense is messiah David's master? Unless he's an angel, he must be on the divine side of the categorical divide, rather than the mundane side. And he's not an angel. So, by process of elimination, he must be the Deity.