yadi mām apratīkāram
aśastraḿ śastra-pāṇayaḥ
dhārtarāṣṭrā raṇe hanyus
tan me kṣemataraḿ bhavet
yadi — even if; mām — me; apratīkāram — without being resistant; aśastram — without being fully equipped; śastra- pāṇayaḥ — those with weapons in hand; dhārtarāṣṭrāḥ — the sons of Dhṛtarāṣṭra; raṇe — on the battlefield; hanyuḥ — may kill; tat — that; me — for me; kṣema- taram — better; bhavet — would be.
It is the custom -- according to kshatriya fighting principles -- that an unarmed and unwilling foe should not be attacked. Arjuna, however, decided that even if attacked by the enemy in such an awkward position, he would not fight. He did not consider how much the other party was bent upon fighting. All these symptoms are due to soft-heartedness resulting from his being a great devotee of the Lord.