Guru Purnima is a day to celebrate the Guru, external and internal. It is a day when we pay homage and respect.  We acknowledge and give thanks to all those who help guide us along the path of remembrance. We open our hearts and shine with love. The purpose of this knowledge in the spiritual traditions is simply moksha, liberation. Further, the purpose of passing on the knowledge is for the compassion towards all living beings, to liberate them and lighten their journey. The day keeps sacred the memory of the great sage Vyasa. Vyasa the ancient saint edited the four Vedas, wrote the 18 Puranas, the Mahabharata and the Srimad Bhagavata.- Brahmanda Purana 1.4.21