According to Saint John Chrysostom, "here they fulfilled that dread commandment which Jesus Christ gave. Yet they did not do this immediately, but only when they had already been expelled. But even this did not harm the disciples. On the contrary, they were still more edified by the word of God. For the suffering of the teacher does not halt the disciple’s zeal, but makes him still more zealous."
"The teachers were persecuted, and they rejoiced." Why? Because the apostles went on to give the same glorious good tidings in other places.
This same glory was being accomplished in those who believed, who had received into themselves the Spirit, the Comforter. He opened to them the whole course of the gospel proclamation, personally comforted them, and filled them with joy in the Lord.
He also filled them with joy in the glory of His preachers of the faith. This glory is not darkened by any persecution, especially not by such a persecution as took place here through superstitious women and noble rich men, whom the Jews, as usual, held in their hands.