Therefore the Lord shall have no joy in their young men: neither shall he have mercy on their fatherless, and widows: for every one is a hypocrite and wicked, and every mouth hath spoken folly. For all this his indignation is not turned away, but his hand is stretched out still.
Isaiah 9:15 The aged and honourable, he is the head: and the prophet that teacheth lies, he is the tail.
Isaiah 9:16 And they that call this people blessed, shall cause them to err: and they that are called blessed, shall be thrown down, headlong.
Isaiah 9:17 Therefore the Lord shall have no joy in their young men: neither shall he have mercy on their fatherless, and widows: for every one is a hypocrite and wicked, and every mouth hath spoken folly. For all this his indignation is not turned away, but his hand is stretched out still.
Isaiah 9:18 For wickedness is kindled as a fire, it shall devour the brier and the thorn: and shall kindle in the thicket of the forest, and it shall be wrapped up in smoke ascending on high.
Isaiah 9:19 By the wrath of the Lord of hosts the land is troubled, and the people shall be as fuel for the fire: no man shall spare his brother.
The verse centers on "mercy", "therefore", "lord", "shall", "young", "neither", and "fatherless". It is saying that the verse draws attention to "mercy" and "therefore", so its meaning should be read from those terms before moving to application.
The nearby context moves from verse 16's "And they that call this people blessed..." into verse 18's "For wickedness is kindled as a fire...", so "mercy" and "therefore" belong inside that flow. 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 "mercy" and "therefore" with trust shaped by these words, not by a vague optimism outside the passage.