Though, I hasten to add, he’s still wrong. Come on! “Throne of David” prophecies are only fulfilled by a literal chair in Jerusalem? Give me a break.
Quite true. There is nothing in the Bible to make us think that the phrase "throne of David" is meant to make us think of a literal seat. The throne of David represents God’s reign over His people. After all, God is the true king of Israel, not a mere man.
You only need to read the passages where this phrase is found to get the sense of how it is to be understood.
"As the Lord has been with my lord the king, even so may He be with Solomon, and make his throne greater than the throne of my lord King David." (1 Kings 1:37) {In this verse a distinction is made between the throne of Solomon and the throne of David. Yet Solomon is said to be heir to the throne of David. Obviously the throne is meant to be symbolic expression.}
"And moreover the king's servants have gone to bless our lord King David, saying, 'May God make the name of Solomon better than your name, and may He make his throne greater than your throne.' Then the king bowed himself on the bed." (1 Kings 1:47) {Obviously throne is meant to represent reign or rule, not a literal seat somewhere.}
"then I will establish the throne of your kingdom over Israel forever, as I promised David your father, saying, 'You shall not fail to have a man on the throne of Israel.'" (1 Kings 9:5) {Here it is spoken of as the throne of Israel}
Acts 2 is confirmation that Jesus has indeed been raised up to sit on the throne of David/Israel, where He presently is, subduing the nations.