Herod keeps his interest in the wise men’s news secret because he does not want the people of Jerusalem to know of his self-interest, or his plans, regarding the birth of the new king.
Herod assumed that the child had been born the moment when the star appeared for the first time (Matthew 2:16). Having learned the place of Jesus’ birth from the Sanhedrin he now wants to know how and when this birth has taken place. He therefore secretly summons the Magi in order to learn more with regard to the time and place of the birth while also avoiding suspicion on the part of the Jewish people because of his peculiar interest in this matter.1 He does this secretly so that the people of Jerusalem, knowing what kind of man Herod was, wouldn’t suspect that he plans on doing something about the arrival of the Messiah.2
7 Then Herod summoned the wise men secretly and ascertained from them what time the star had appeared.