Then, surrounded by the Pharisees, Jesus asked them a question:
"What do you think about the Messiah? Whose son is he?" They replied, "He is the son of David."
Jesus responded, "Then why does David, speaking under the inspiration of the Holy Spirit, call him Lord? For David said,
'The LORD said to my Lord, Sit in honor at my right hand until I humble your enemies beneath your feet.'
References for Matthew 22:44
Since David called him Lord, how can he be his son at the same time?"