Right now, Arjuna's mind is pulled in many directions. Scriptures promise many things — rituals for heaven, duties for honor, sacrifices for prosperity. Which voice should he follow? Krishna says: when your intellect stops swaying between these competing claims and stands absolutely still in samadhi, that is yoga.
This stillness is not stubbornness. A stubborn person clings to one view out of ego. A person in samadhi has passed through all the arguments and arrived at a place of direct knowing. The noise has settled. What remains is clarity — not borrowed from any external voice, but arising from within.