ARJUNA REFERRED TO URVASHI AS HIS MOTHER

Arjuna reaches Indraloka & Urvashi curses him to become Impotent 

Arjuna acquired many divine weapons from the deities after getting blessed by Lord Shiva. As per Indra, he had to go to Indraloka for which Indra sent his charioteer Matali to bring him to heaven or Svarga in his chariot. Arjuna entered Amaravati there and was eagerly welcomed by all the deities. He presented his prayers to all and received blessings from them. Indra hugged his son Arjuna and provided him to sit down on his throne next to him. All the Apsaras amused them by dancing there. Arjuna stayed in Indrabhawan and learned about weapons. He spent five years there except for seeing his cherished brothers. Then Indra suggested he learn singing musical instruments and dancing from his Gandharva king Chitrasen for relaxation. Arjuna became fluent in that too.

One day seeing Arjuna attracted to Apsara Urvashi, Indra asked Chitrasena to present Urvashi in service of Arjuna. Chitrasena as per Indra's advice admired the greatness of Arjuna in front of Urvashi and asked her to serve him. Urvashi was satisfied to hear this. She wished to be intimate with Arjuna. Therefore she took a bath, wore fragrant garlands, and shining fairly clothes, and then entered the palace of Arjuna. Arjuna being coy at that time could no longer face her. He simply touched her feet and offered her prayers. Arjuna asked her the motive for approaching there respectfully. Urvashi was astonished to see such behaviour. She elaborated on her conversation with Chitrasena. 

She additionally mentioned, "Arjuna! Due to the fact that You looked at me whilst all other apsaras including me were dancing in front of you and all deities, that was observed by your father Indra at that moment. Consequently, he has sent me here to serve you. I also wish to be intimate with such a meritorious individual like you."

Arjuna was embarrassed to hear such, he closed his ears with his palm and told her, "I respect you just like the Shachi Devi; spouse of Indra, and that time I looked at you with a sense of respect only. I worship you just like my Mother Kunti and Indrani. It would even be a sin to consider my guru's wife in such a way. "

Urvashi cited him, "Do not step aside now as I am an apsara only! I can by no means take the place of any seniors. Being an Apsara I can certainly do this act barring any hesitation and there is no blunder for doing this."

Arjuna civilly requested her to return by way of saying that he had regarded her solely as a mother similar to Kunti, Shachi, and Madri. Urvashi got irritated and cursed him that he would emerge as impotent and stay with females as a dancer. After that, she left that palace. Arjuna anxiously explained the whole lot to Chitrasena. 

Indra came to understand this and he advised his son, "The curse that Urvashi has given you will turn out to be valuable. Since You along with your brothers and Draupadi need to continue to be in disguise in the forest for the 13th year of your exile period, as an impotent it will be helpful for you throughout such period. After finishing one yr you will again acquire your manhood." After listening to this from Indra, Arjuna was relieved. He accomplished all his learnings there in heaven.

This is how he got cursed via Urvashi and later in Virata Parva of Mahabharata, he spent the one year of his exile as Brihannala at King Virata’s Matsya Kingdom. He taught singing and dancing to the Princess Uttara there.

Ref:mahabharata book Vana Parva

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