Once upon a time Lord Brahma, not seeing an expansion in his creation became very worried. A heavenly voice instructed him to commence creation with the help of copulative activities. But since all the incarnation of Shiva had been males till then, therefore lord Brahma was finding it impossible.
Lord Brahma contemplated on the form of Shiva and Shakti. Lord Shiva became very pleased with him and appeared in his form of ‘Ardhanarishwar (half male half female). Left side of his body resembled like a woman while the right side appeared like a man. Lord Brahma worshipped this form of Shiva.
Lord Shiva then separated the feminine part of his body and thus manifested mother Shakti. Lord
Brahma worshipped her and requested to bestow such power by which he could create a woman.
Goddess Shakti blessed him by saying – ‘So be it’ and vanished. This way Lord Brahma became capable of commencing copulative creation.