Our Lord was now in the temple, and he took the opportunity for instructing the scribes and Pharisees concerning his person and his dignity. Thus, as ever, he returned good for evil. He here taught them that the Messiah was not a mere man, as they supposed, but that he was i both God and man, and that therefore they ought not to wonder or to be offended because he called himself the Son of God.
St. Matthew (Matthew 22:42) more fully gives their answer first, namely, that "Christ is the Son of David." They should have said that, as God, he was the Son of God, according to those words, "Thou art my Son; this day have I begotten thee;" but that, as man, he was the Son of David.
Their answer was very different from that of Peter: "Thou art the Christ, the Son of the living God." But they wanted the Divine knowledge which the disciples had gained.