Bhagavad Gita, Chapter 18, Verse 6

But even these works, O Pârtha, should be performed, leaving attachment and the fruits; such is My best and certain conviction.

Krishna calls this his real, final word here, not one opinion among several still open for debate.

Naming this his definite and supreme verdict closes off any lingering ambiguity from the earlier disagreement. Real certainty is offered instead of continued debate.