Vishnu Sahasranama stotra are thousand names of Vishnu said by Bhishma to Yudhishtira and other Pandavas. This occurs in Mahabharata while there are other versions of thousand names in Garuda Purana, Skanda Purana and Padma Purana. These thousand names which are a conversation between Bhishma and Yudhishtira are popular.
The 187th name among these thousand names is "Govinda". Many acharyas like Adi Shankaracharya, Parashara Bhattar, Baladeva Vidyabhushana etc., have written commentaries on Vishnu Sahasranama stotra. My question is about Adi Shankaracharya's commentary on the name Govinda. Adi Shankaracharya gives the following meanings to the name: (From Vishnu Sahasranama With The Bhasya of Sankaracharya)
The Mahabharata, Mokshadharma (San., 343-41) says: "I first knew (vinda) the Earth (go) which was carried away and hidden in a cave (by an Asura), hence I am praised by the appellation 'Govinda' by Gods, and Scriptures." The Harivamsa (76-45 and 279-49) says: "I am Indra (Lord) over the Devas, thou art lord over the cows, hence the world will ever praise Thee as, Govinda '; speech is named 'Go,' and since thou conferest speech, 0 Lord, the Sages call you 'Govinda'."
Ka Go+ Vide has the following tell meanings: Go
1. Svarga (Heaven). He transcends the Heaven.
2. Arrows (He knows all the weapons).
3. Cattle. He is the leader of the ignorant ones.
4. Speech. He is to be known by the Vedas.
5. Thunderbolt; He has the Vajra marks on his feet.
6. Quarters; He is known in all quarters.
7. eyes; He is in the person residing in the eyes.
8. The sun ; He is in the form of the Sun.
9. Earth; He recovered the Earth from the Titans.
10. Waters; His seat is in the waters.
And Vid, to know.
My question is on the fifth meaning Adi Shankara gives. He comments "Thunderbolt; He has the Vajra marks on his feet".
Where is it stated that Vishnu (or Krishna) has marks of Vajra (thunder bolt) on his feet?
It is generally believed that Lord Krishna has various markings on his feet as stated in the above question. Is Adi Shankara referring to them? What verse or incident is he indirectly referring to?