Because wherever Lord Vishnu appears, it becomes Bhuvaikuntha. Bhuvaikuntha means ‘the Vaikuntha on earth.’ This Vaikuntha is not merely a loka. But it is the highest loka out of all the lokas. Even the Mahabharata says the same. This loka is none other than a form of Lakshmidevi Herself. Wherever Paramatma goes, Lakshmidevi comes with Him, and hence spreads happiness and abundance everywhere. Vaikuntha means, ‘where there is no sorrow or obstacles.’ Plus, Bhagavan is the remover of all these obstacles and sorrows; that’s why He is known as Hari. And hence, wherever He comes is known as Bhuvaikuntha.
In Pandharpur, Lord Vishnu appeared as Vitthala for His dearest devotee, Pundalika. Even before that, it was known as the Lohadanda kshetra. Because there lived a demon by the name Dindirava. He was exceptionally powerful and caused nuisance everywhere. Therefore, Lord Vishnu incarnated as Mallikaarjuna in that kshetra and fought Dindirava with a loha danda (iron rod), and killed him there. That’s why the kshetra was known as Lohadanda Kshetra. This is mentioned in the Padma Purana.
Whereas if we talk about what happened later, then there was a devotee of Lord Vishnu by the name of Pundalika. Earlier, he didn’t serve his old-aged parents and used to spend time with his wife. Once, when he went to Kashi with his parents, there he halted at the ashrama of Kukkuta Rishi. There, at night, Pundalika saw that Ganga, Yamuna and Sarasvati were cleaning the Sage’s ashrama. He asked them who they were, and they introduced themselves as Ganga, Yamuna, and Sarasvati. They instructed him to serve his parents. Then he realized the importance of his parents and served them with Bhakti. Once, he was in his house and was serving his parents, considering it as Hariseva. Krishna in the Bhagavad Gita says, ‘One must do their nihita karma, considering it as His seva. This pleases Him very much.’
So, pleased by His devotion, Lord Krishna appeared there, stood near His doorstep, and called Pundalika’s name. He said, “Who is there?” Bhagavan said, “I am Bhagavan ShriKrishna.” At this, Pundalika said, “I am serving my parents now, so I cannot come out now. For the time being, you can wait on the brick I am giving you.” By saying this, Pundalika threw a brick near Bhagavan. Bhagavan came and stood on the brick, put His hands on His waist, and stood there, waiting for His dear devotee Pundalika to come to Him. Later on, Pundalika came there and was awestruck to see Krishna there. He bowed down to Krishna and praised Him.
Krishna was pleased by the devotion of Pundalika and hence blessed Him to stay with Him forever. And then He transformed into a shila pratima. That vigraha of Panduranga Vitthala was a Svayambhu moorti. The Supreme Lord Vitthala came there and stayed there. Seeing Vitthala standing on the brick, Rukmini Devi, the Jaganmaata, also came there and stood beside Lord Vitthala. Lord Vitthala, in His Gopala Vitthala form, is holding the kaathi (stick), which is even today visible in the vigraha. In one hand, He is holding a shankha, and in the other hand, He is holding a lotus flower, and has kept His hands on His waist. He has His navel as the origin of Lord Brahma, Srivatsa Chinha, where Sage Bhrigu had kicked Him. He also has the Kaustubha jewel on His neck and wears Kireeta on His head.
Thus, Vitthala and Rukmini are standing there today too, waiting for their dear devotees to come and have their darshan on the banks of the Chandrabhaaga river. Now, what does Vitthala mean? Vitthala traditionally means the one who is standing on the brick. But as per the Shaastras, there is a meaning. Vi means Agyaana or Vipareeta gyaana. ‘Thha’ means the one who removes that agyaana, and ‘la’ means the one who gives the correct knowledge.
So, overall, Vitthala means the one who removes agyaana and provides us with correct knowledge, even to the devatas led by Lord Brahma. Panduranga also has a meaning as per the Shaastras. Panduranga is the combination of two words, ‘Pandura’ and ‘Anga’. Pandura means pure, and anga means body. The one who has the purest body (Pavitraanaam pavitram yo mangalaanaam cha mangalam - VSN, Mahabharata, Anushasana Parva).
Saying the name Vitthala is good for the heart because it is said that the Thhakaara in Vitthala is good for the heart, and chanting it keeps our heart healthy and reduces the chances of heart attacks and cardiac diseases.
Vaikuntha is a place where there is 0 sorrow, 0 tension, and 100% attention of Bhagavan towards you. But you are different from Him. Okay, so here too, if you do darshan of Bhagavan Vitthala, who is the Supreme Being, you will have 0 sorrow, 0 tension, and 100% attention and anugraha from Vitthala, who is worshipped by Brahma and Rudra. That’s why Pandharpur is known as Bhuvaikuntha. Not only Pandharpur, but wherever Bhagavan stayed, is Bhuvaikuntha. Pandharpur, Vrindavana, Mathura, Dwaraka, Ayodhya, Badarinath Dhaam, Puri Jagannath, Dandakaranya, Panchavati, Srimushnam, SriRangam, Tirupati (Sheshachala Parvata), Kanchi Varadaraaja Swamy, Udupi SriKrishna, Bhadrachala SeetaRamachandra Swamy, etc., all are Bhuvaikuthas and are Svayamvyakta Kshetras.
Hope this helps!
Jay SriRam!
Pundalika Varade Hari Vitthala! SriDnyanadeva Tukaram! Pandharinaath Maharaj ki Jay!
ShriRukminiVitthala Abhinna ShriKrishnarpanamastu!