Judah and Ephraim were the two largest tribes of Israel. Joshua was of the tribe of Ephraim; perhaps the Ephraimites carried from that some sense of entitlement that they should play more of a leadership role. When Jeroboam of the tribe of Ephraim rebelled against King Rehoboam, Mannasseh and all the other northern tribes followed his lead.
From that point on the prophets referred to the whole rebellious northern kingdom and Joseph, or Ephraim, just as all the tribes united in the southern kingdom were called Judah. And Joseph was now once more separated from his brethren. That is the affliction of Joseph the prophet Amos was referring to in Amos 6:1-6.
Elijah and Elisha were both natives of the northern kingdom, used of God to warn the people and call them to return unto the true worship of the Lord. Hosea and Amos were from Judah and called of God to call the people of the northern kingdom to repentance.
Jonah was also of the northern kingdom. The only mention of him, beside the book which carries his name, is found in 2 Kings 14:25. This is the account of Jeroboam II retaking the northern part of Israel from the Syrians, as prophesied by Jonah.
2 Chronicles 21:12-15 records the letter sent to King Jehoram of Judah by Elijah: “Thus saith the LORD God of David thy father, Because thou hast not walked in the ways of Jehoshaphat thy father, nor in the ways of Asa king of Judah, but hast walked in the way of the kings of Israel, and hast made Judah and the inhabitants of Jerusalem to go a whoring, like to the whoredoms of the house of Ahab, and also hast slain thy brethren of thy father’s house, which were better than thyself: behold, with a great plague will the LORD smite thy people, and thy children, and thy wives, and all thy goods: and thou shalt have great sickness by disease of thy bowels, until thy bowels fall out by reason of the sickness day by day.”
The only other connection of Elijah to Judah is that when he felt his life threatened by Jezebel he crossed into Judah, left his servant there and continued on to Mount Horeb.
There is a revealing incident in the life of Elisha when King Jehoram of Israel and King Jehoshaphat of Judah were preparing for battle and called on Elsha to enquire of the Lord on their behalf. Elisha replied to the king of Israel: “As the LORD of hosts liveth, before whom I stand, surely, were it not that I regard the presence of Jehoshaphat the king of Judah, I would not look toward thee, nor see thee” (2 Kings 3:14).
All of this is pretty conclusive evidence that the prophets regarded Judah as the people of God and Israel, led by Ephraim, to be apostate. Yet God had called them to minister to the people of apostate Israel to draw them back into full fellowship with His people.
Hosea spoke of a time when the two houses of Israel would be reunited. During the Babylonian captivity the prophet Ezekiel bemoans the unfaithfulness of the shepherds in chapter 34. Verse 11says: “For thus saith the Lord GOD; Behold, I, even I, will both search my sheep, and seek them out.”
The sending of the 70 by Jesus to seek out the lost sheep of the house of Israel should be seen as part of the fulfilment of Ezekiel’s prophecy. Note that he is referring to sheep, that is children of God. The lost condition referred to means that they had no shepherd, not that they were spiritually lost. When the Bible speaks of the saved and the lost it refers to them as sheep and goats. The sheep will enter heaven, the goats will be turned away.
There are multitudes of people in the world today who are unsaved and need to hear the gospel and see it being lived out in the lives of true children of God. But there are also the lost sheep, the children of God who wander through the wilderness of the world because they do not have a shepherd. They are also a mission field. Jesus said: “And other sheep I have, which are not of this fold: them also I must bring, and they shall hear my voice; and there shall be one fold, and one shepherd” (John 10:16).