Bhagavad Gita
1.38

कथं न ज्ञेयमस्माभिः पापादस्मान्निवर्तितुम् | कुलक्षयकृतं दोषं प्रपश्यद्भिर्जनार्दन ||३८||

kathaṁ na jñeyam asmābhiḥ pāpād asmān nivartitum kula-kṣhaya-kṛtaṁ doṣhaṁ prapaśhyadbhir janārdana

Translation

Why should we, who can clearly see the sin of destroying a family, not turn away from this terrible deed, O Janardana?

Interpretation

Arjuna's argument is: since we can see what they cannot (the sin of destroying family), we have an even greater obligation to step back. The logic sounds sound, but it assumes that abstaining from battle is sinless. Krishna will show that for a Kshatriya, abstaining from righteous battle is itself a sin.