Matthew 2:3

He was troubled. The catalogue of atrocities by Herod, particularly the murder of various members of his immediate family whom he suspected of plotting to do away with him and usurp his throne, testifies eloquently to the feelings of his heart upon hearing that One destined to be “King of the Jews” had been born (see pp. 61, 62). The seeming reticence of the priests to divulge information concerning the Messianic prophecies, which the wise men had no doubt mentioned, led Herod to suspect the priests of conniving with the wise men in a plot to unseat him from his throne, perhaps by exciting a popular tumult. Furthermore, it is probable that Herod himself knew of the popular expectation that a prince was to be born in Judea who was destined to rule the world. Not only so; he appears to have regarded himself as the Messiah and to have had secret longings to rule the world (see Joseph Klausner, The Messianic Idea in Israel, p. 374).

All Jerusalem. It is little wonder the whole city was “troubled” also, because its residents were too familiar with the atrocities of which Herod was capable. Fearing a popular tumult, he might well decree the slaughter of hundreds or thousands of the people.