Gopastami is the festival when Lord Krishna together with His cowherd boyfriends officially took up the task of tending cows as cowherds.

It is stated in the Kārttika-māhātmya section of the Padma Purāṇa:

“The eighth lunar day of the bright fortnight of the month of Kārttika is known by authorities as Gopāṣṭamī. From that day, Lord Vāsudeva served as a cowherd, whereas previously He had tended the calves.”

Nanda Maharaj together with other Vrajavasis gave this charge to their children. Mother Yashoda and the other gopis were worried about Krishna’s soft lotus feet which would wander over the thorny forest of Vrindavan without any shoes but barefoot.

“Sukadeva Gosvami said: ‘Thus the Vrndavana forest was filled with transparent autumnal waters and cooled by breezes perfumed with the fragrance of lotus flowers growing in the clear lakes. The infallible Lord, accompanied by His cows and cowherd boyfriends, entered that Vrindavana forest.’”

Lord Krishna showed how to love and take care of the cows. Following in His footsteps, cows and bulls are worshipped by the devotees in various ISKCON centers and all over Vrindavan.

One can serve the cows by bathing them, feeding them. One can offer special worship to their home deities also. This is a fun festival for us, and sometimes you will see ladies dressed as cowherd boys as well. 

 image source: ISKCON Desire Tree

For more on Gopastami, please read:  Why Does Srimati Radharani Give Us Darshan Of Her Divine Lotus Feet On Gopastami?