The word used in Ps 110:1 is not Adonai. Adonai is always used for God. It means Lord God. The word used in Ps 110:1 is adoun (or adown), a secular title meaning lord, as in master:
"The LORD [YHWH ] says to my Lord [adoun] : Sit at My right hand..." (NAB)
By capitalizing the word lord, Christian translators suggest it is Jesus Christ, and Mat 22:43-44 serves as "proof".
Christian lexicons claim the word adoun is also used for God but Jewish sources and my own search tell me this word was only used to mean master, who is in charge, as in Joshua 3:13, but not as a title for deity.
So, in that context, the Levite priest, who is supposed to sing the Psalm liturgically, is saying "The LORD said to my master (David): sit at My right hand...". It's hard to believe that Jesus would have misunderstood this linguistically and contextually as it appears from Mat 22.
So adown can be used either as a title or simply as meaning master as Sarah said of her “master”.
“So, in that context, the Levite priest, who is supposed to sing the Psalm liturgically, is saying “The LORD said to my master (David): sit at My right hand...”. It's hard to believe that Jesus would have misunderstood this linguistically and contextually as it appears from Mat 22.”
The Lord said to David's master, “Thou [art] a priest for ever after the order of Melchizedek.” (vs. 4).
No Levite priest ever called David “.. a priest for ever after the order of Melchizedek”, nor did David refer to himself as such.
It's not Jesus who has trouble understanding who is being called Lord at Ps 110.
This is a prophetic psalm..it points to Christ..the son of David.. This is a resurrection prophecy .The jews yet to this day are blinded..it does not matter what they see as a historic reading..they,like all the unsaved were and are unable to see prophesy or types in the OT..