Krishna had refused to take up arms in the Kurukshetra war, but His presence on the side of the Pandavas was beneficial to them in many ways, because Krishna, the Supreme One, guided them in times of crisis. He also helped them find their way out of tricky situations, explained V.S. Karunakarachariar, in a discourse.
Arjuna was a man who had taken many vows. Two of them landed him in trouble. One vow was that he would kill anyone who insulted his skill in archery. Another vow was that he would kill anyone who hurt Yudhishthira. During the battle with the Kauravas, Yudhishthira is injured and comes back to camp dejected. Arjuna and Krishna arrive, and seeing Arjuna, Yudhishthira gives vent to his anger. He insults Arjuna and says that Arjuna must give up his bow, if he cannot kill the enemy.
Arjuna is bound by his vow to kill anyone who insults his bravery. So he is now in the terrible situation of having to kill his own brother.
As always he looks to Krishna for help, and Krishna does not let him down. It is suggested that Arjuna should insult Yudhishthira. Arjuna accuses Yudhishthira of having brought the family to this pass. Was it not his gambling that had seen the family lose its hard earned wealth? Was it not Yudhishthira’s gambling that had resulted in Draupadi being shamed? As Arjuna lists Yudhishthira’s mistakes, Yudhishthira hangs his head in shame. Can there be anything more troubling, than having one’s sins pointed out to one, and being told that one is responsible for the sorrow of others? It is akin to death. Thus Arjuna by insulting Yudhishthira has killed him in a metaphoric sense.
But what about the other vow, whereby Arjuna should kill anyone who kills his brother? Shouldn’t Arjuna now therefore kill himself? Again, Krishna comes to the rescue. It is suggested that Arjuna praise himself.
Self praise is also akin to death, and thus by praising himself, Arjuna has committed suicide, and so the other vow is also kept by him. Thus we find that at every turn Krishna helps the Pandavas.