# How do they say ... son?
"Why do people say ... son?" Jesus uses a question to make the scribes think about who the Messiah is. Alternate translation: "Let's think about them saying ... son." or "I will talk about them saying ... son."
# David's son
"King David's descendant." The word "son" is used here to refer to a descendant. In this case it refers to the one who would reign over God's kingdom.