In order to understand this prophecy, a little background is in order. G-d had stated to Hoshea that the Jews had sinned. Hoshea responded by suggesting to Hashem that He exchange the Jews for another nation. As a Prophet, it was Hoshea’s responsibility to follow Moshe’s example and fight on behalf of the nation, not reaffirm their guilt and sins. In essence, Hoshea had spoken Lashon Harah about the Jews.
As a part of Hoshea’s training, Hashem instructed him to marry a woman who was a prostitute. He fathers three children whom he gives unusual names reflecting his personal frustration with the Jews. His oldest is named Yizrael – The G-d Who plants. His second child, a daughter, he names Lo Ruchamah – One who does not deserve mercy. His third child, a boy, he named Lo Ami – Not My nation.
Hashem then told him to send away his wife and children. Hoshea begged G-d to rescind His order because he loved his family and did not want to be apart from them. G-d then says to him, "Isn’t your wife a prostitute, and don’t even know if your children are yours? Yet you love them! So too is my relationship with the Jews. No matter how they betray me I still love them and do not want to be apart from them!"
Hoshea understood the lesson and changed his entire attitude toward the Jews. Instead of presenting the angry demeanor of harshness and judgment, Hoshea prophesied some of the most beautiful and optimistic prophecies that we have.
The final words of the Haftorah capture the eternity of G-d’s love for His Chosen People. "I shall marry you to Me forever…"