Arjuna said: Oh Madhusūdana! This yoga you have described as equality — due to the restlessness of the mind, I do not see lasting stability in it.

Arjuna expresses the practical difficulty. The mind (cañcala) is restless, agitated, like a jumping monkey. The sāmya (equality) that Kṛṣṇa describes seems theoretically admirable, but impossible to maintain.

This is a genuine objection: the human mind is unstable by nature. How to achieve sthiti sthirām (firm stability) in something so fluctuating?