In plain words
Let us not have this war; let us go home,” he said. Kṛṣṇa, showing anger: “Shame, coward! I was sitting quietly and you urged Me on to war, and now you are frightened! In that case, why should you have made ready for war at all?” He rebuked him. To turn him towards his duty, He taught him the Bhagavad Gītā. Kṛṣṇa's teaching entered his heart and gave him the strength he needed; Arjuna set about the battle; but he could not stand up to Bhīṣma's onslaught. Then, meaning to give Arjuna courage, Kṛṣṇa rushed forward, saying, “I shall kill this Bhīṣma.” Arjuna: “Kṛṣṇa! ‘I will not take up a weapon, I will not fight,’ You vowed. If You fight now, it will be as though You have broken Your word. You must not break Your word for my sake,” he prayed. Seeing Kṛṣṇa rushing towards him, Bhīṣma folded his hands.
As He leapt down, the gleam of His earrings spread over the whole expanse of the sky; as He sprang, the earth, unable to bear the worlds held in His belly, shook under the weight of those worlds; taking up the discus in His hand, in the speed of His coming the yellow cloth upon Him slipped; “I trusted You; do not make my strength a mockery; forgive me,” Kirīṭi said, and held Him back again; flashing like a lion that springs upon an elephant, “Today I shall kill Bhīṣma and save you; let go, Arjuna,” He cries, and through the shower of my arrows the God who comes rushing on is my refuge.
“Kṛṣṇa Paramātma, who comes to kill me, is Himself my refuge,” he said. So great a jñāni, so supreme a devotee, was Bhīṣmācārya.