We hear God the Father speaking to God the Son. "The Lord said to my Lord, 'Sit at My right hand, till I make Your enemies Your footstool"' (v. 1). This is quoted often in the New Testament. It talks about when our Lord Jesus Christ returned to heaven and was enthroned at the right hand of the Majesty.
What does this Father-Son conversation say to us? First, it speaks of our Lord's majesty. He has returned to heaven in glory. He had prayed, "Father, glorify me together with Yourself, with the glory I had with You before the world was" (John 17:5), and God did that. God the Father gave God the Son His majesty, and now He is the King-Priest in heaven. "You are a priest forever according to the order of Melchizedek" (v. 4). Nowhere in the Old Testament do we find a priest on a throne, but Jesus in His majesty is both our King and our Priest. As our King, He tells us what to do. As our Priest, He gives us the strength to do it.
Psalm 110 also speaks of victory--He has won the battle. "Sit at My right hand, till I make your enemies Your footstool" (v. 1). That's about as low as you can get. Our Savior is victorious. He has won every battle. He is the Conqueror, the King of kings and Lord of lords. There is nothing for us to fear.
This psalm also speaks about His ministry. Most people on thrones have others serve them. Not so with Jesus. He serves us.
Finally, the psalmist speaks of our security. "He ever lives to make intercession" for us (Heb. 7:25). As long as He lives, we live--and that's forever.