When Krishn ruled Dwarika, he wanted to fulfill promise given to Hanuman during his previous incarnation of Ram that he (Ram) will meet Hanuman once more in the next incarnation.
Dwarika was protected by the sharp razor edged disk - Sudarshan Chakr. Along with sharpness it has tremendous temperature which can kill anyone. It is the eternal weapon of Krishn. Hence the chakr developed ego that no one in the universe can stand against its strength.
Satyabhaama was one of the queens of Krishn. She was extremely beautiful. She developed ego that no one is more beautiful than her.
Garud the eagle, who is the vehicle of Krishn, is a super fast in its movements and developed ego that no one could be faster than him.
Krishn decided to four jobs through one act. He told Garud to go and bring Hanuman. So went Garud and told Hanuman,'Shri Krishn is calling you.' Hanuman said,'Krishn? No! I am servant of Ram. I won't come'. Garud flew back and told Krishn about it. Krishn said, 'Oh! Yes! Tell him that Ram has called him.' The same Ram assumed the form of Krishn in the next incarnation.
Garud again traveled to Hanuman and told him that Ram had called him Hanuman was looking very very old. So Garud asked Hanuman to sit on his back so that both of them would reach Dwarika fast. Hanuman said,'You proceed, I will follow.' But Garud insisted which infuriated Hanuman and he caught Garud with his hand and threw it with such a force that Garud fell long in the sea.
Hanuman then went to Dwarika. Chakr said ,'Stop! Who are you?' Not happy with this behavior Hanuman piked up the chakr and put it in the own mouth.
Hanuman then reached Krishn's palace. Meanwhile Krishn turned himself into Ram. Nothing was required flute was replaced with bow and arrow and stood straight as ram did. The problem was of Sita. Krishn asked Satyabhaama to dress like Sita and both of them welcomed Hanuman.
On seeing Ram, Hanuman said,'My Lord! You are alone? Where is mother Sita? And who is this maid servant sitting beside you?' Satyabhaama realized that she was nowhere near to Sita. Her ego vanished.
Then Krishn asked Hanuman,'What is in your mouth?' Hanuman took out the Sudarshan chakr and said 'Lord! This toy was troubling me!' Krishn smiled and looking at chakr said,' Ok! Leave it free now.' Chakr was too happy to be free from the clutches of Hanuman and it too realized that its sharpness and temperature was not invincible.
Then Garud came panting. To its surprise, Hanuman was present in the palace before him! Garud too realized that there is someone who is much more faster them him.
It is true that there is no ego once soul seeks God. But this drama was staged by Krishn and his associates to warn all against developing ego. Ego is the enemy that does not allow happiness to flow in and keeps the soul unsatisfied through out. In addition, all sorts of sins are committed to keep ego intact. The outcomes of these sins is then sufferings of billions of years. Hence no decisions should be taken just to keep pride and ego intact.