Two Sanskrit texts — a Panduranga Mahatmya of about nine hundred verses in the Skanda Purana, in two recensions, and one of twelve hundred in the Padma Purana — tell how the god came to stand at Pandharpur. Pundalik had been a bad son until a change of heart made him his parents' servant. Krishna, pleased, came to visit him. Pundalik was washing his parents' feet and would not stop for a god; he pushed a brick out through the doorway so that the visitor need not stand in the mud, and said he would come when he had finished. Krishna stood on the brick with his hands on his hips to wait, and is waiting yet. The image at Pandharpur is that pose, and the brick is under his feet.
The Marathi poets — Sridhara, Prahlada Maharaj, Mahipati in the Bhaktavijaya, Bahinabai, Namdev — retell the brick story as the founding act of the Varkari path, in which the god who waited for a devotee is walked to every year from across Maharashtra. In their hands Pundalik is the first of the saints and the brick is the proof that service to parents outranks even a god's visit; three versions of the legend circulate among them.
Vernacular devotional framing; Pundalik as the first Varkari saint; the Badva priests' ritual view is a separate strand.
Sources: Pundalik — Wikipedia; Vithoba — Wikipedia
Krishna came to Pundalik's door, was told to wait on a brick while the son served his parents, and stayed; the Varkari saints sang to him as Vitthal.
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Jain tellings keep Rama and Krishna as great men in a fixed roster of sixty-three: Lakshmana kills Ravana, Rama becomes a monk, and Krishna is Neminatha's cousin.
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Taraka can die only to a son of Shiva, and Shiva sits in grief and meditation after Sati.
An image made by Vishnu himself passes from Brahma to King Sutapas to Uddhava, who has Brihaspati and Vayu install it in Kerala after Dwarka sinks.
Madhva finds the Krishna image in a lump of clay; the low-caste singer Kanakadasa, barred from the temple, sees the god turn west through a crack that became the Kanakana Kindi.