When thinking about who is the ardent devotee of Lord Narayana, one can remember none other than the great Saint Naradha. However, his overwhelming devotion on Lord Narayana put him to feel shy of ashamed.
Once someone praised Naradha that Kamadeva had ruined even the meditation of the Almighty Lord Shiva but could not break your meditation on Lord Narayana. The stranger also added that you are far superior to Lord Shiva.
On hearing his words, haughtiness in Naradha has increased. The bloated Naradha thought like “yes I am superior to Lord Shiva, right”.
Lord Narayana revealed the changes in his devotee Naradha, hence decided to teach him a lesson and bring him in his way.
For this purpose, Lord Vishnu ordered spouse Lakshmi Devi to incarnate on the earth. Hence Lakshmi Devi was given birth to the wife of King Ambarish who was ruling Ayodhya, named her Sreemathi and grows her in his way with lots of love on her.
As Naradha was wandering landed on earth, reached the kingdom of Ambarish. There he saw his daughter and was fascinated by the beauty of Sreemathi and desired to get her to be his wife. He mentioned his desire with Ambarish.
On hearing the words of Naradha, Ambarish lost his mind. He scared for what to reply. Went to a dilemma like neither he can accept Naradha’s request, nor he can give his word without the consent or knowing the desire of his daughter.
Then Ambarish got an idea / solution and replied like ‘Swami I will arrange a Swayamvar (Proposal Ceremony)’. If my daughter likes you there, I do not have any problem to marry her to you. ‘
Naradha felt okay with Ambarish idea of Swayamvar but doubted whether Sreemathi will accept him as his spouse or not. So he went and surrendered before Lord Shiva to give a solution for his situation. Hearing the enthymeme of Naradha, Lord Shiva replied with a smile that “who is there most beautiful than Lord Narayana”. If you looks more beautiful exactly like Lord Narayana then the Princess will definitely be yours.
On the suggested advice of Lord Shiva, went straight to Vaikunta. Naradha narrated Lord Vishnu about what Lord Shiva told him. So my lord, I humbly request you to bless me with such a charming beauty exactly like you when I appear before Sreemathi in the swayamvar. Lord Vishnu stayed as he was with a cheerleading smile. Taking the smile as the graces of the lord, Naradha left the place.
Naradha attended the Swayamvar and saw Sreemathi standing with a garland. When the turn of Naradha came, Sreemathi got scared on fear on seeing him in the monkey faced like monk and inattentively put the garland on a charming person neck who just stood beside him.
As soon as Sreemathi put the garland both vanished from that place. Naradha confused about what’s happening around him there. He could see Lord Vishnu come before his eyes and Sreemathi turned to him, both vanished that blown away his mind.
Meanwhile he stunned to see his face reflection in the waters of a pond thus realised what was happened. Lord Vishnu only changed his form like a monkey. He grew anguished, furious for the ploy played by Lord Vishnu in taking away the princes whom he loved a lot.
So Naradha cursed Lord Vishnu that he will also suffer the same languishment of wife separation and will finally reunite with the help of a monkey.
It is fact that Naradhas furiousness on Lord Vishnu, but as on time passed, Naradha realised the philosophy behind the play of Lord Vishnu.
This is because, Lord Vishnu, Lakshmi Devi born as Rama and Sita, suffered the pain of separation and reunited with the help of Hanuman.
Thus the curse of Naradha became the main cause for the key events of the Ramayana.