Will God's mercy ever depart from Israel?
God's mercy will never depart from Israel. He will discipline them for their sin, and they will face the greatest tribulation discipline, but He is not destroying the nation or turning His back on them forever, unlike taking the kingdom from Saul.
Les teaches that the word "but" in verse 15 signals the flip side: Israel will commit iniquity, yet God says His mercy will never depart from them, or from him. The analogy is Saul, from whom God took the kingdom. Regardless of how far Israel falls into wickedness, God will discipline them—including the greatest discipline any people will ever face in the tribulation—but He is not destroying the nation. He has set them aside, but has not turned His back on them forever. Even after the crucifixion, in early Acts, Peter addresses the children of Israel and pleads with them to respond to the fact that the one they crucified was their Messiah. Nationally they rejected it, though some believed.
But my mercy shall not depart away from him, as I took it from Saul, whom I put away before thee.
More Questions
In 2 Samuel 7:15, does God ever take His mercy away from Israel?
Even though Israel falls short and is often unbelieving, God says 'My mercy shall not depart from them,' so his mercy to Israel is permanent.