Chapter2- Sloka 4
arjuna uvāca
kathaṃ bhīṣmam ahaṃ saṃkhye droṇaṃ ca madhusūdana |
iṣubhiḥ pratiyotsyāmi pūjārhāv ari-sūdana || 4 ||
(2.4)
arjuna uvāca- Arjuna said; madhusūdana- O killer of the demon Madhu; ari-sūdana- O destroyer of enemies of those who take your shelter; saṃkhye- in this battle; kathaṃ- how; ahaṁ pratiyotsyāmi- can I fight to hurt; iṣubhiḥ- with arrows; bhīṣmaṃ- grandfather Bhīṣma; droṇaṃ ca- and ācārya Droņa; pūjārhāu- worthy of my worship;
Purport
Again, due to affection and compassion towards his relatives, Arjuna perceived his kṣatriya dharma contrarily as adharma. He thus became fearful and disturbed. Unable to understand and reflect on the valuable advice of Paramapuruṣa, Arjuna continued to express his concern, “O Madhusūdana, Arisūdana! In this battle, how can I hurt with arrows grandfather Bhīṣma, ācārya Droṇa and others who are worthy of my worship."
ca The 'ca' used here is an anukta samuchchayam. When Arjuna said, 'bhīṣmaṃ, droṇaṃ ca', the 'ca' referred to all his other relatives like Duryodhana and his brothers, Śalya, etc, who were in the Kaurava army. (anukta samuchchayam refers to all those who are not explicitly mentioned here, but are a part of the overall scene under discussion or the text at large.)
madhusūdana, ari-sūdana By addressing Kṛṣṇa as Madhusūdana and Arisūdana, Arjuna’s intention is to bring to Kṛṣṇa's notice that HE attacked and killed demon Madhu and such others but not even once did HE attack Sāndīpani Muni and HIS other ācāryas with arrows.
ahaṃ With the word 'ahaṃ', Arjuna’s intention is to ask Kṛṣṇa, 'How can I, who is born in a good lineage with a good upbringing, perform this unforgiving act of attacking ācāryas and respectable relatives?'