It is the custom - according to ksatriya fighting principles - that an unarmed and unwilling foe should not be attacked. Arjuna, however, in such an enigmatic position, decided he would not fight if he were attacked by the enemy. BG 1972 purports

Expressions researched:
"that an unarmed and unwilling foe should not be attacked. Arjuna, however, in such an enigmatic position, decided he would not fight if he were attacked by the enemy"

BG Chapters 1 - 6

It is the custom—according to kṣatriya fighting principles—that an unarmed and unwilling foe should not be attacked. Arjuna, however, in such an enigmatic position, decided he would not fight if he were attacked by the enemy. He did not consider how much the other party was bent upon fighting.

BG 1.45, Translation and Purport:

I would consider it better for the sons of Dhṛtarāṣṭra to kill me unarmed and unresisting, rather than fight with them.

It is the custom—according to kṣatriya fighting principles—that an unarmed and unwilling foe should not be attacked. Arjuna, however, in such an enigmatic position, decided he would not fight if he were attacked by the enemy. He did not consider how much the other party was bent upon fighting. All these symptoms are due to softheartedness resulting from his being a great devotee of the Lord.