Verse 5 makes it very clear Who is “Adoni” is in verse 1. Here it reads:
“The Lord at your Right Hand”
Which is a further reference to “Adoni”, Who is at the Right Hand of “Yahweh”. In verse 5 the Hebrew word used in the greater majority of manuscripts, is “Adonay”, and not “Adoni”. “Adonay” is always used in the Old Testament for Almighty God, and never for any humans or heavenly beings. There are about 20 Hebrew Masoretic Text, that reads in verse 5, “Yahweh”. Either Name is that used for the Eternal, Unchanging, Self-Existing, God of the Holy Bible. And here it is clearly used for the Lord Jesus Christ!
Some, who cannot accept the fact, that Jesus Christ is here identified as Almighty God, have suggested that verse 5 does not mean what it actually says. As Dr Cheyen says in his Commentary:
“The description in vv. 2, 3 is resumed. The Lord is Jehovah (surely not the king), who is invisibly standing at His viceroy's right hand” (p.303)
Others try to read, “the Lord is at your Right Hand”, which is not in the Hebrew.
The “Yahweh” of verse 1, now changes places with “Adon”, and is on His Right Hand! This is no more than conjecture and the rejection of what the Bible plainly Teaches. There is NO Scripture passage that says that God the Father is at the Right Hand of Jesus Christ. What it does say in verse 5, is that the “Adon”, which some of the Masoretic manuscripts, by the Jews, read “Yahweh”, is COEQUAL with “Yahweh”. Verse one can be translated as “Yahweh says to my Yahweh”.
The passages in the Gospels, when read with Psalm 110, is one of the clearest and strongest, testimonies by The Lord Jesus Christ, on His Absolute Deity. These passages also show that the God of the Holy Bible is not “Unitarian”, as there are here TWO distinct “Persons” Who are EQUALLY Almighty God.