Had heard these things - Had heard of their coming, and of the star, and of the design of their coming.
He was troubled - Herod had obtained the kingdom by great crimes, and by shedding much blood. He was therefore easily alarmed by any remarkable appearances; and the fact that this star appeared, and that it was regarded as proof that a King of the Jews was born, alarmed him. Besides, it was a common expectation that the Messiah was about to appear, and he feared that his reign was about to come to an end. He therefore began to inquire in what way he might secure his own safety and the permanency of his government.
All Jerusalem - The people of Jerusalem, and particularly the friends of Herod. There were many in Jerusalem to whom the coming of the Messiah would be a matter of joy; but all of Herod’s friends would doubtless be alarmed at his coming.