Bhagavad Gita
2.10

तमुवाच हृषीकेशः प्रहसन्निव भारत | सेनयोरुभयोर्मध्ये विषीदन्तमिदं वचः ||१०||

tam uvācha hṛṣīkeśhaḥ prahasann iva bhārata senayos ubhayor madhye viṣīdantam idaṁ vachaḥ

Translation

O descendant of Bharata, in the middle of both armies, Krishna smiled and spoke these words to the grief-stricken Arjuna.

Interpretation

Krishna smiles ('prahasann iva') — a gentle, perhaps wry smile. He is not dismissive; he is compassionate and supremely confident. He has seen this confusion before, in many souls across countless ages. His smile is the smile of the one who knows the answer before the question is asked.