Arjun: Urge the steeds, O Madhav to where Bhishma is. I’ll do as you say. I will slay Bhishma But instead of slaying Bhisma, Arjuna breaks the string of his own bow Krishna realizes that Arjun wasn’t fighting like he should, he jumps from the chariot and bolts towards Bhishma
माधवस तु वचः शरुत्वा फल्गुनस्य महात्मनः न किं चिद उक्त्वा सक्रॊध आरुरॊह रथं पुनः
Arjun then pleads Krishna to not break His vow and promises to kill Bhisma himself. Shri Krishna doesn’t say a word to Arjuna, goes back and mounts the chariot.