SB 1.9.37
sva-nigamam apahaya mat-pratijñam
rtam adhikartum avapluto rathasthah
dhrta-ratha-carano ’bhyayac caladgur
harir iva hantum ibham gatottariyah
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
Fulfilling my vow and sacrificing His own promise, He got down from the chariot, took up its wheel, and ran towards me hurriedly, just as a lion goes to kill an elephant. He even dropped His outer garment on the way.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
The Battle of Kuruksetra was fought on military principles but at the same time in a sporting spirit, like a friend’s fight with another friend. Duryodhana criticized Bhismadeva, alleging that he was reluctant to kill Arjuna because of paternal affection. A ksatriya cannot tolerate insults on the principle of fighting. Bhismadeva therefore promised that the next day he would kill all five Pandavas with special weapons made for the purpose. Duryodhana was satisfied, and he kept the arrows with him to be delivered the next day during the fight. By tricks Arjuna took the arrows from Duryodhana, and Bhismadeva could understand that this was the trick of Lord Krsna. So he took a vow that the next day Krsna would have to take up weapons Himself, otherwise His friend Arjuna would die. In the next day’s fighting Bhismadeva fought so violently that both Arjuna and Krsna were in trouble. Arjuna was almost defeated; the situation was so tense that he was about to be killed by Bhismadeva the very next moment. At that time Lord Krsna wanted to please His devotee, Bhisma, by keeping Bhisma’s promise, which was more important than His own. Seemingly He broke His own promise. He promised before the beginning of the Battle of Kuruksetra that He would remain without weapons and would not use His strength for either of the parties. But to protect Arjuna He got down from the chariot, took up the wheel of the chariot and hurriedly rushed at Bhismadeva in an angry mood, as a lion goes to kill an elephant. He dropped His covering cloth on the way, and out of great anger He did not know that He had dropped it. Bhismadeva at once gave up his weapons and stood to be killed by Krsna, his beloved Lord. The fighting of the day was thus ended at that very moment, and Arjuna was saved. Of course there was no possibility of Arjuna’s death because the Lord Himself was on the chariot, but because Bhismadeva wanted to see Lord Krsna take up some weapon to save His friend, the Lord created this situation, making Arjuna’s death appear imminent. He stood before Bhismadeva to show him that his promise was fulfilled and that He had taken up the wheel.