BG 1.29-31

My whole body shudders; my hair is standing on end. My bow, the Gāṇḍīv, is slipping from my hand, and my skin is burning all over. My mind is in quandary and whirling in confusion; I am unable to hold myself steady any longer. O Krishna, killer of the Keshi demon, I only see omens of misfortune. I do not foresee how any good can come from killing my own kinsmen in this battle.

BG 1.36-37

O Maintainer of all living entities, what pleasure will we derive from killing the sons of Dhritarasthra? Even though they may be aggressors, sin will certainly come upon us if we slay them. Hence, it does not behoove us to kill our own cousins, the sons of Dhritarashtra, and friends. O Madhav (Krishna), how can we hope to be happy by killing our own kinsmen?

BG 1.36-37

O Maintainer of all living entities, what pleasure will we derive from killing the sons of Dhritarasthra? Even though they may be aggressors, sin will certainly come upon us if we slay them. Hence, it does not behoove us to kill our own cousins, the sons of Dhritarashtra, and friends. O Madhav (Krishna), how can we hope to be happy by killing our own kinsmen?

BG 2.5

It would be better to live in this world by begging, than to enjoy life by killing these noble elders, who are my teachers. If we kill them, the wealth and pleasures we enjoy will be tainted with blood.

BG 2.6

We do not even know which result of this war is preferable for us—conquering them or being conquered by them. Even after killing them we will not desire to live. Yet they have taken the side of the sons of Dhritarasthra, and now stand before us on the battlefield.

BG 18.17

Those who are free from the ego of being the doer, and whose intellect is unattached, though they may slay living beings, they neither kill nor are they bound by actions.