Passage
Thy first father sinned, and thy teachers have transgressed against me.
Thy first father sinned, and thy teachers have transgressed against me.
Isaiah 43:25 I am, I am he that blot out thy iniquities for my own sake, and I will not remember thy sins.
Isaiah 43:26 Put me in remembrance, and let us plead together: tell if thou hast any thing to justify thyself.
Isaiah 43:27 Thy first father sinned, and thy teachers have transgressed against me.
Isaiah 43:28 And I have profaned the holy princes, I have given Jacob to slaughter, and Israel to reproach.
The verse centers on "first", "father", "sinned", "teachers", "transgressed", and "against". It is saying that the verse draws attention to "first" and "father", so its meaning should be read from those terms before moving to application.
The nearby context moves from verse 26's "Put me in remembrance and let us..." into verse 28's "And I have profaned the holy princes...", so "first" and "father" 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 "first" and "father" with trust shaped by these words, not by a vague optimism outside the passage.