The OP is referring to, perhaps, to the following sloka from the 3rd chapter of BG.
ज्यायसी चेत्कर्मणस्ते मता बुद्धिर्जनार्दन।
तत्किं कर्मणि घोरे मां नियोजयसि केशव।।3.1।।
Arjuna said O Janardana, if knowledge is held to be superior to action
by You, then why do You engage me in action that is terrible, O Kesava
The following slokas are to ...