Bhagavad Gita 2.10: tam uvāca hṛṣīkeśaḥ, prahasann iva bhārata, senayor ubhayor madhye, viṣīdantam idaḿ vacaḥ SYNONYMS: tam — unto him; uvāca — said; hṛṣīkeśaḥ — the master of the senses, Kṛṣṇa; prahasan — smiling; iva — like that; bhārata — O Dhṛtarāṣṭra, descendant of Bharata; senayoḥ — of the armies; ubhayoḥ — of both parties; madhye — between; viṣīdantam — unto the lamenting one; idam — the following; vacaḥ — words.

TRANSLATION: O descendant of Bharata, at that time Krishna, smiling, in the midst of both the armies, spoke the following words to the grief-stricken Arjuna.

The answer comes in Bhagavad Gita, the first text book of counseling. When grief ridden Arjuna approaches him he starts his counseling in happy and smiling mood. Arjuna was grief-filled, sad and rebellious. Yet Krishna smiled. The word in the Gita is prahasann, which means to smile before laughing (beginning to laugh). It was not a weak or full smile or a sarcastic grimace, but a very positive smile. About half of the worry of a patient is relieved if he/she sees the doctor smiling or the relatives see a smile on the face of a doctor coming out of operation theater. In a situation similar to that in Bhagavad Gita, a smile also gives confidence to the patient (Arjuna) that his doctor (Krishna) has understood his problem fully and has a solution to his problem. Buddha is also shown smiling and Goddess Kushmanda is also shown with a smiling face.