Once (in around 1951) Śrīla Gurudeva stayed at Śrī Uddhāraṇa Gauḍīya Maṭha, which was the headquarters of Śrī Gauḍīya Vedānta Samiti at that time. From there he went out and preached śuddha-bhakti everywhere. The sevā and pūjā in the Maṭha, as well as Śrī Navadvīpa-dhāma parikramā and other activities, used to run on whatever alms came from madhukarī. Before Śrī Dhāma Navadvīpa parikramā, I [the author] went with parama-pūjyapāda Śrī Śrīmad Nārasiṁha Mahārāja to Śrī Rāmapura and other towns near Kolkata to preach and beg alms.
After preaching and performing bhikṣā for fifteen days we returned to Śrī Uddhāraṇa Gauḍīya Maṭha, having collected a total of two hundred and fifty rupees, which at that time was a large sum of money. As soon as I arrived, I offered my praṇāma at paramārādhyatama Śrīla Gurudeva’s lotus feet. After giving his blessings, he asked, “How was the preaching?”
“The preaching went very well,” I replied. “We collected about two hundred and fifty rupees.” Gurujī was very pleased. Sometime later pūjyapāda Nārasiṁha Mahārāja came before Gurujī, offered his praṇāma and put the donation in Gurujī’s hand. Śrī Gurudeva asked, “How much is it?”
“Two hundred and twenty-five rupees,” replied pūjyapāda Nārasiṁha Mahārāja.
“Where are the remaining twenty-five rupees?” asked Śrīla Gurudeva.
“I have kept some rupees for my personal expenses,” replied Mahārāja.
“Bring those donated rupees right now and give them to me,” said Śrī Gurudeva.
Śrīpāda Nārasiṁha Mahārāja was somewhat angry and said, “Can’t we keep even a few rupees for our immediate expenses?”
“First please kindly give them to me.”
Pūjyapāda Mahārāja somewhat resentfully went to his bhajana-kuṭī, brought back the remaining twenty-five rupees, and threw them down in front of Śrīla Gurudeva. Gurujī picked up the money, counted it and then returned those very same rupees.
“If you are just going to return them, then what was the point in taking them in the first place?” asked Śrīpāda Nārasiṁha Mahārāja.
Śrī Gurudeva became quite grave and said, “The food and wealth of sensuous people contains poison which ordinary people cannot digest. It has been written in śāstra that when a sādhaka eats food from a sense enjoyer, his heart becomes wicked and it is not possible to remember Bhagavān with such a disturbed mind. Therefore sādhakas should always be careful. Śrī Raghunātha dāsa Gosvāmī is direct proof of this. He did not accept the money sent by his own father, because although his father appeared to be a Vaiṣṇava, he was actually not (vaiṣṇava- prāya). Even advanced sādhakas have been deviated and have fallen from the realm of bhajana due to eating the food of sensuous people. That is why I have taken this money from you. It was acquired from sense enjoyers, and therefore it was mixed with poison. Now I have purified it and I am giving it back to you. There is no danger in it any more.
“Disaster is guaranteed if even one paisa that has been collected in the name of Śrī Hari, Guru and Vaiṣṇavas is used in one’s own service. I do not use even a single paisa from donations for my own purposes. Who can engage donated wealth in the service of Hari, Guru and Vaiṣṇavas? Only a highly qualified Vaiṣṇava who has offered his body, mind, words and everything at the feet of śrīla gurudeva and the Supreme Lord, who is unconditionally surrendered at the lotus feet of Bhagavān, and who is empowered in bhajana. Ordinary temple devotees cannot.”
When pūjyapāda Nārasiṁha Mahārāja heard this, he became thoroughly ashamed and all misgivings were dispelled from his heart. Bowing his head, he said with complete humility, “Please forgive me. I never took this matter so seriously. Whatever you are saying is completely correct. I will follow this instruction the rest of my life.”
The lesson to be learned from this is that one should never at any time utilize for one’s own enjoyment money or commodities received from worldly people. One should offer them at the divine feet of gurudeva or equally elevated Vaiṣṇavas, because such Vaiṣṇavas can engage these commodities in the service of Bhagavān. Otherwise, their poison is deadly for the sādhaka. Śrīman Mahāprabhu has said:

viṣayīra anna khāile malina haya mana
malina mana haile, nahe kṛṣṇera smaraṇa

Śrī Caitanya-caritāmṛta (Antya-līlā 6.278)

When one eats food offered by sensuous or worldly people, the mind becomes contaminated, and in that state one cannot remember Kṛṣṇa.

pratigraha kabhu nā karibe rāja-dhana
viṣayīra anna khāile duṣṭa haya mana

mana duṣṭa haile nahe kṛṣṇera smaraṇa
kṛṣṇa-smrti vinā haya niṣphala jīvana

Śrī Caitanya-caritāmṛta (Ādi-līlā 12.50–51)

One should never accept alms from royalty or wealthy people because when one eats such food the mind becomes polluted. A polluted mind cannot remember Kṛṣṇa, and without remembrance of Kṛṣṇa one’s whole life is a failure.

Another day, Śrī Kṛtiratna Prabhu (Śrīla Gurudeva) saw Bābājī Mahārāja in his bhajana-kuṭī deeply absorbed in bhajana. Many devotees who were taking his darśana were also offering donations, and one of them started to gather up the coins. Bābābjī at once scolded him, saying, “Tho, paisā tho. Jekhānakāra paisā sekhāna tho. Utpātera kauḍī citpāte jaya – Don’t touch the money. Leave it wherever it is. Corrupt money is the reason one falls down.” All the actions of a mahāpuruṣa are for the welfare of the world, and their instructions are extremely important for true practitioners of bhakti. Those who act in accordance with their instructions will gradually progress in bhajana. Their lives will become blissful and they will achieve perfection in their sādhana-bhajana.

―Śrīla Bhaktivedanta Nārāyaṇa Mahārāja (Ācārya Kesarī Śrī Śrīmad Bhakti Prajñāna Keśava Gosvāmi – His Life and Teachings)
Image/Art made possible by Pixabay.com