Today is the holy day of the disappearance of Mukund Datta Thakur. He used to live in Chittagong from there he came to Nabadvipa and became a fellow student of Mahaprabhu at Gangadas Pandit’s Tol. Mahaprabhu used to ask questions, they used to give answers, Mahaprabhu used to disprove their answers and again ask questions. Because of that, all the devotees used to fear Him.

Mahaprabhu is a scholar of grammar. One day Mukund Datta asked him about Alankar of vyakaran (grammar). Mahaprabhu gave a very nice answer to it. Mukund Datta was surprised, an ordinary person cannot have such knowledge. He thought if he would have been a devotee then, how nice it would be! We do not like that he is arguing so much. Mahaprabhu told me I would be a great devotee, and you all would see it later. When Mahaprabhu returned from Gaya, he showed intense ecstatic feelings of love for the Lord. Mahaprabhu when used to cry in separation for Lord, Mukund Datta used to sing songs appropriate for that mood, as he was Madhu mangal in Krishna Lila and used to sing for the pleasure of Krishna. Listening to Mukund Datta, Advait Acharya and all others used to get bliss. He gave two important teachings. Pundarik Vidhyanidhi, who came from Chatt Gram was there. He was acting like a materialistic person to hide his devotion to the Lord. But Mukund Datta knew that he was a great devotee, Vrishbhanu Maharaj, father of Radharani Himself in Krishna Lila. Mahaprabhu addressed him as a father, even before he met him. Mukund Datta took Gadadhar pandit to Pundarik to have his darshan but seeing him engaged in materialist activities, even gadadhar pandit who was a brahmachari by birth and had staunch faith, his faith also disturbed. He became upset and he told Mukund Datta, “What is this, you told me you would take me to have darshan of a great devotee, but is he a devotee? He is engaged in enjoying worldly things.” Then Mukund Datta understood the feelings of Gadadhar Pandit and he narrated a shloka from Bhagavatam,

Aho bakiyam stankala kutam jighamsayapayayad apy
Asadhvi labhe gatim dhatry ucitam tatoyamkam
vadayalum saranam vrajema

The sister of the demon Bakasur, the evil putana came to kill Krishna with kalkuta poison applied to her breast. She showed little so-called motherly affection, but still, he awarded her the position of a wet nurse. Is there anyone else I can take shelter of who is more merciful than this Krishna?

As soon as he heard, Pundarika Vidyanidhi fell to the floor in a swoon and various transcendental symptoms became manifest in him. Gadadhar Pandit realized that he had committed an offense. He began to regret it. Later on the advice of Mahaprabhu, he took Initiation from Pundarika Vidyanidhi.

One more important incident showing the Lord teaches through His devotees. Mukund had so much deep affection for Mahaprabhu that when He took sanyas, Mukand felt so much pain. He sang kirtan when Mahaprabhu took a bath before sanyas, though Mukund had so much love for Him. When Mahaprabhu exhibited His Maprakash Lila for 21 hours, he was bound by deep affection and love, had called all the devotees and gave His audience in the form they had desired and awarded boons to them but he did not give this opportunity to Mukunda, who is very dear to Him. All devotees were surprised, why He was not showering mercy on Mukund?

Srivas Pandit requested Mahaprabhu to be merciful to Mukunda, to which the Lord replied, “Mukunda is a pretentious wretch. His mind is not fixed. He sometimes is a perfect figure of humility approaching Me holding a straw in his teeth, but the next moment he comes to strike Me with an iron rod. Sometimes he associates with devotees and sometimes associating with non-devotees he strikes Me with an iron rod. And therefore he is not eligible for the darshan of My divine form, as the controller of everything.”

Hearing Mahaprabhu's harsh words, Mukunda was deeply aggrieved and decided to quit his body. But before he did he had Srivas Pandit inquire Mahaprabhu if there is any chance of getting His darshan ever? Mahaprabhu replied, "He will get My darshan after ten million of his births." Hearing Mahaprabhu's reply, Mukunda forgot himself completely and danced while uttering repeatedly, "Mahaprabhu's words will never be untrue". In a moment Mukunda's ten million births were destroyed. Mahaprabhu freed him from his offenses and exhibited His opulent form at that very moment. Mahaprabhu, accepting His defeat, spoke, “I perpetually reside on Mukunda’s tongue. Wherever I will appear, you will get the service to sing for Me".
(Chaitanya Bhagavat 2.10.260)

Mukunda condemned himself for not having any devotion in him. He sang the glories of devotion and through an example explained the terrifying state of being a non-devotee.

Mahaprabhu is giving a teaching here. He makes a devotee as a medium to teach the worldly people. In Bengali, there is a saying, the meaning of which is, that the mother-in-law teaches the daughter-in-law by instructing her daughter. Thus the Supreme Lord imparts teachings to the worldly people by instructing His devotees.