Vishnupurana 5.12.18

5.12.18

bhārāvataraṇe sāhyaṃ sa te vīraḥ kariṣyati
sa rakṣaṇīyo bhavatā yathātmā madhusūdana //

When Indra had, by direction of the kine, inaugurated Krishńa, the husband of Śachí said to him affectionately, "I have thus performed what the cows enjoined me. Now, illustrious being, hear what farther I propose, with a view to facilitate your task. A portion of me has been born as Arjuna, the son of Pritha: let him ever be defended by thee, and he will assist thee in bearing thy burden. He is to be cherished by thee, Madhusúdana, like another self." To this Krishńa replied, "I know thy son, who has been born in the race of Bharata, and I will befriend him as long as I continue upon earth. As long as I am present, invincible Śakra, no one shall be able to subdue Arjuna in fight. When the great demon Kansa has been slain, and Arisht́a, Keśin, Kuvalayápíd́a, Naraka, and other fierce Daityas, shall have been put to death, there will take place a great war, in which the burden of the earth will be removed. Now therefore depart, and be not anxious on account of thy son; for no foe shall triumph over Arjuna whilst I am present. For his sake I will restore to Kunti all her sons; with Yudhisht́hira at their head, unharmed, when the Bhárata war is at an end."