Psalm 110:1; “The Lord says to my lord: Sit at my right hand, till I make your enemies your footstool.”
This Psalm is most likely written by an officer in David’s army. It says here; The Lord, (in Hebrew Y-H-W-H) says to my lord, (in the sense of master). This is literally translated: Y-H-W-H says to my master: etc. This applies to David, just like the next verse, “The Lord sends forth from Zion your mighty scepter. Rule in the midst of your foes.” This is what King David did, God made his enemies a footstool to him, and he ruled from Zion (Jerusalem). Verse 5 and 6: “The Lord is at your right hand, He will shatter kings on the day of his wrath. He will execute judgment among the nations, filling them with corpses.” King David slaughtered many of his enemies, as written in this Psalm, but all these things that were never done by Jesus. Therefore it makes no sense to say that this applies to Jesus and not to king David.
Here is the explanation of the great Jewish sage from the Middle Ages, rabbi Moshe ben Nachman, a.k.a. the Ramban:
King David was the composer who wrote the Psalms with the aid of the holy spirit. He composed them for the purpose of having them sung before the altar of God. He himself did not sing them, nor was he permitted to do so, for that function was forbidden to him by law of the Torah. (Deuteronomy 18:6-7) Insted, he gave the Psalms to the Levites, so that they would sing them. This is clearly written in the book of I Chronicles 16:7 Therefore, King David perforce expressed the psalm in the language appropriate for utterance by the Levites. Thus, if King David had said; “The Eternal said to me”, the levites repeating these words would be uttering falsehood. Instead, it is proper for the Levite to say in the Temple: “The Eternal saith unto my lord: (that is to King David) Sit thou at My right hand.” The purport of the term ‘sitting’ is to state that the Creator, blessed be He, will protect him during his lifetime and that He will save him and cause him to prevail over his enemies. So it was, for he lifted up his spear against eight hundred, whom he slew at one time. This is the right hand of God. It is also written of David: “And Your right hand has holden me up.” Psalm 18:36. It is similarly written: “The right hand of the Almighty does valiantly. The right hand of the Eternal is exalted.” Psalm 118:15 Regarding Moses our teacher, peace be upon him, it is written: “He caused His glorious arm to go at the right hand of Moses.” Isaiah 63:12 And Moses said at the fall of pharaoh: “Thy right hand, O Eternal, dashes the enemy in pieces.” Exodus 15:6