Due to the quantum nature of Bible prophecy, this verse has meanings at different levels. At the literal level it is talking about watchmen calling out from the hills of the territory of Ephraim just north of Jerusalem. However, on a deeper level it could be referring to the northern Kingdom of Israel (Lost 10 Tribes) calling out from where they were exiled and scattered to return to their original homeland. Mountains and hills in the Bible often are used symbolically as kingdoms. So the verse in this context is saying that there will be watchmen from the kingdoms of the 10 tribes associated with Ephraim calling out and wanting to come home to Zion. These “Watchmen on the hills of Ephraim” are those of the northern kingdom of Israel waking up to who they are and desiring to return to the Promised Land and to their God, the God of Israel.
So who are the “Watchmen on the hills of Ephraim” today? There is a hint of who they are in the actual Hebrew text of this verse. The Hebrew word translated as Watchmen in the word Notzrim. According to Wikipedia, “In Modern Hebrew, the word "Notzrim" (נוצרים) is the standard modern word for Christians, but Meshiykhiyyim (Hebrew: משיחיים) is used by many Christians of themselves, as in the BFBS New Testament of Franz Delitzsch; 1 Peter 4:16 "Yet if any suffer as ha-Meshiykhiyyim (Hebrew: משיחיים), let them not be ashamed, but let them glorify God in that name." In the Hebrew New Testament Tertullus' use of "Nazarenes" (Acts 24:5) is translated "Notzrim", and "Jesus of Nazareth" is translated "Yeshu ha Notzri".”
Consequently, today in Israel, Notzrim (Watchmen) is the word that the Israelis use for the term Christian. I don’t believe that this is a coincidence, but a divine clue as to what group of people includes the Lost 10 Tribes. They are found within Christianity. Specifically, I believe they are the Christians that have a strong affinity and love for the Jews and the State of Israel. Their eyes are being opened to who they are and a movement referred to as Hebraic Restoration has been building momentum for over a decade now.
It is time for the rest of the “Watchmen on the Hills of Ephraim” to wake up to who they are and make the call – “Arise, and let us go up to Zion, to the Lord our God.”