Passage
But there will be no more gloom for her who was in anguish; in earlier times He treated the land of Zebulun and the land of Naphtali with contempt, but later on He shall make it glorious, by the way of the sea, on the other side of Jordan, Galilee of the Gentiles.
Nearby Context
Isaiah 9:1 But there will be no more gloom for her who was in anguish; in earlier times He treated the land of Zebulun and the land of Naphtali with contempt, but later on He shall make it glorious, by the way of the sea, on the other side of Jordan, Galilee of the Gentiles.
Isaiah 9:2 The people who walk in darkness Will see a great light; Those who live in the land of the shadow of death, The light will shine on them.
Isaiah 9:3 You shall multiply the nation, You shall make great their gladness; They will be glad in Your presence As with the gladness of harvest, As men rejoice when they divide the spoil.
Study Lenses
The verse centers on "gloom", "anguish", "earlier", "times", "treated", "land", and "zebulun". It is saying that the verse draws attention to "gloom" and "anguish", so its meaning should be read from those terms before moving to application.
The next verse adds "The people who walk in darkness Will...", so "gloom" and "anguish" should be read forward into that movement. In Isaiah context, the local focus is the Holy One of Israel, judgment and restoration, the servant of the LORD, and Zion's hope.
A plain takeaway is to answer the verse's own emphasis on "gloom" and "anguish" with trust shaped by these words, not by a vague optimism outside the passage.