Just like Moses went up the mountain and came down from the mountain, Jesus went up the mountain in chapter 5:1, now he came down from the mountain (Καταβάντος δὲ αὐτοῦ ἀπὸ τοῦ ὄρους). Matthew continued to use the phrase great crowds followed or accompanied him (ἠκολούθησαν αὐτῷ ὄχλοι πολλοί). A new phase in the life of Jesus was to begin. The time of mountain teaching had ended. It was time for action.
Once again, Joseph was warned in a dream (χρηματισθεὶς δὲ κατ’ ὄναρ), without the explicit mention of the angel of the Lord. Joseph found out that the son of King Herod (ἀντὶ τοῦ πατρὸς αὐτοῦ Ἡρῴδου), Archelaus, (23 BCE-16 CE) was now in charge in Judea (ἀκούσας δὲ ὅτι Ἀρχέλαος βασιλεύει τῆς Ἰουδαίας). He was afraid to go back there (ἐφοβήθη ἐκεῖ ἀπελθεῖν) to Judea, since maybe King Herod’s son would be after his child just like his father. Actually, Herod Archelaus only lasted about 10 years before the Romans took the title away from him in 6 CE. Thus, Joseph decided to withdraw to the district of Galilee (ἀνεχώρησεν εἰς τὰ μέρη τῆς Γαλιλαίας), without explicitly being told to do so. Galilee was a rocky terrain region in northern Israel. Originally, it was part of the tribal regions of Naphtali, Dan, and Asher, but later it was part of the northern kingdom of Israel, with a Phoenician presence and influence. In the Roman times, Galilee was clearly separate from Judea. Many of the events in the life of Jesus would take place there, even though Herod Antipas, the other son of King Herod, ruled Galilee from 4 BCE-39 CE.