The Lord's early life was recorded by one of His chief devotees and contemporaries, namely Śrīla Murāri Gupta, a medical practitioner of that time, and the latter part of the life of Śrī Caitanya Mahāprabhu was recorded by His private secretary Śrī Dāmodara Gosvāmī, or Śrīla Svarūpa Dāmodara, who was practically a constant companion of the Lord at Purī. These two devotees recorded practically all the incidents of the Lord's activities, and later on all the books dealing with the Lord, which are above mentioned, were composed on the basis of kaḍacās (notebooks) by Śrīla Dāmodara Gosvāmī and Murāri Gupta.
(Srimad Bhagavatam------introduction).

The chief historical sources for the life of Śrī Kṛṣṇa Caitanya are the kaḍacās (diaries) kept by Murāri Gupta and Svarūpa Dāmodara Gosvāmī. Murāri Gupta, a physician and close associate of Śrī Kṛṣṇa Caitanya's, recorded extensive notes on the first twenty-four years of His life, culminating in His initiation into the renounced order, sannyāsa. The events of the rest of Caitanya Mahāprabhu's forty-eight years were recorded in the diary of Svarūpa Dāmodara Gosvāmī, another of His intimate associates.
Śrī Caitanya-caritāmṛta is divided into three sections, called līlās, a word that literally means "pastimes"—the Ādi-līlā (recounting the early period of Lord Caitanya's pastimes), the Madhya-līlā (recounting the middle period), and the Antya-līlā (recounting the final period). The notes of Murāri Gupta form the basis of the Ādi-līlā, and Svarūpa Dāmodara's diary provides the details for the Madhya- and Antya-līlās.
(Sri Caitanya Caritamrta------foreward).

Murāri Gupta, the twenty-first branch of the tree of Śrī Caitanya Mahāprabhu, was a storehouse of love of Godhead. His great humility and meekness melted the heart of Lord Caitanya.
Śrī Murāri Gupta wrote a book called Śrī Caitanya-carita. He belonged to a vaidya physician family of Śrīhaṭṭa, the paternal home of Lord Caitanya, and later became a resident of Navadvīpa. He was among the elders of Śrī Caitanya Mahāprabhu. Lord Caitanya exhibited His Varāha form in the house of Murāri Gupta, as described in the Caitanya-bhāgavata, Madhya-khaṇḍa, Third Chapter. When Śrī Caitanya Mahāprabhu exhibited His mahā-prakāśa form, He appeared before Murāri Gupta as Lord Rāmacandra. When Śrī Caitanya Mahāprabhu and Nityānanda Prabhu were sitting together in the house of Śrīvāsa Ṭhākura, Murāri Gupta first offered his respects to Lord Caitanya and then to Śrī Nityānanda Prabhu. Nityānanda Prabhu, however, was older than Caitanya Mahāprabhu, and therefore Lord Caitanya remarked that Murāri Gupta had violated social etiquette, for he should have first shown respect to Nityānanda Prabhu and then to Him. In this way, by the grace of Śrī Caitanya Mahāprabhu, Murāri Gupta was informed about the position of Śrī Nityānanda Prabhu, and the next day he offered obeisances first to Lord Nityānanda and then to Lord Caitanya. Śrī Caitanya Mahāprabhu gave chewed pan, or betel nut, to Murāri Gupta. Once Śivānanda Sena offered food to Lord Caitanya that had been cooked with excessive ghee, and the next day the Lord became sick and went to Murāri Gupta for treatment. Lord Caitanya accepted some water from the waterpot of Murāri Gupta, and thus He was cured. The natural remedy for indigestion is to drink a little water, and since Murāri Gupta was a physician, he gave the Lord some drinking water and cured Him.

When Caitanya Mahāprabhu appeared in the house of Śrīvāsa Ṭhākura in His Caturbhuja mūrti, Murāri Gupta became His carrier in the form of Garuḍa, and in these pastimes of ecstasy the Lord then got up on his back. It was the desire of Murāri Gupta to leave his body before the disappearance of Caitanya Mahāprabhu, but the Lord forbade him to do so. This is described in the Caitanya-bhāgavata, Madhya-khaṇḍa, Chapter Twenty. When Śrī Caitanya Mahāprabhu one day appeared in ecstasy as the Varāha mūrti, Murāri Gupta offered Him prayers.
(Sri Caitanya Caritamrta------1:10:49------translation and purport).

Śrīla Murāri Gupta never accepted charity from friends, nor did he accept money from anyone. He practiced as a physician and maintained his family with his earnings.
It should be noted that a gṛhastha (householder) must not make his livelihood by begging from anyone. Every householder of the higher castes should engage himself in his own occupational duty as a brāhmaṇa, kṣatriya or vaiśya, but he should not engage in the service of others, for this is the duty of a śūdra. One should simply accept whatever he earns by his own profession. The engagements of a brāhmaṇa are yajana, yājana, paṭhana, pāṭhana, dāna and pratigraha. A brāhmaṇa should be a worshiper of Viṣṇu, and he should also instruct others how to worship Him. A kṣatriya can become a landholder and earn his livelihood by levying taxes or collecting rent from tenants. A vaiśya can accept agriculture or general trade as an occupational duty. Since Murāri Gupta was born in a physician's family (vaidya-vaṁśa), he practiced as a physician, and with whatever income he earned he maintained his family. As stated in Śrīmad-Bhāgavatam, everyone should try to satisfy the Supreme Personality of Godhead through the execution of his occupational duty. That is the perfection of life. This system is called daivī-varṇāśrama. Murāri Gupta was an ideal gṛhastha, for he was a great devotee of Lord Rāmacandra and Caitanya Mahāprabhu. By practicing as a physician he maintained his family and at the same time satisfied Lord Caitanya to the best of his ability. This is the ideal of householder life.
(Sri Caitanya Caritamrta------1:10:50------translation and purport).

As Murāri Gupta treated his patients, by his mercy both their bodily and spiritual diseases subsided.
Murāri Gupta could treat both bodily and spiritual disease because he was a physician by profession and a great devotee of the Lord in terms of spiritual advancement. This is an example of service to humanity. Everyone should know that there are two kinds of diseases in human society. One disease, which is called adhyātmika, or material disease, pertains to the body, but the main disease is spiritual. The living entity is eternal, but somehow or other, when in contact with the material energy, he is subjected to the repetition of birth, death, old age and disease. The physicians of the modern day should learn from Murāri Gupta. Although modern philanthropic physicians open gigantic hospitals, there are no hospitals to cure the material disease of the spirit soul. The Kṛṣṇa consciousness movement has taken up the mission of curing this disease, but people are not very appreciative because they do not know what this disease is.
(Sri Caitanya Caritamrta------1:10:51------translation and purport).

One day Śrī Caitanya Mahāprabhu felt the ecstasy of the boar incarnation and got up on the shoulders of Murāri Gupta. Thus they both danced in Murāri Gupta's courtyard.
One day Caitanya Mahāprabhu began to cry out, "Śūkara! Śūkara!" Thus crying out for the boar incarnation of the Lord, He assumed His form as the boar incarnation and got up on the shoulders of Murāri Gupta. He carried a small gāḍu, a small waterpot with a nozzle, and thus He symbolically picked up the earth from the depths of the ocean, for this is the pastime of Lord Varāha.
(Sri Caitanya Caritamrta------1:17:19------translation and purport).

Śrī Caitanya Mahāprabhu, with great humility, sent some Jagannātha prasādam and a cloth from Lord Jagannātha to His mother through Śrīvāsa Ṭhākura. When the Lord bade farewell to Rāghava Paṇḍita, Vāsudeva Datta, the residents of Kulīna-grāma and other devotees, He praised them for their transcendental qualities. Rāmānanda Vasu and Satyarāja Khān asked some questions, and Lord Śrī Caitanya Mahāprabhu instructed them that all householder devotees must engage themselves in the service of Vaiṣṇavas exclusively devoted to chanting the holy name of the Lord. He also instructed the Vaiṣṇavas from Khaṇḍa, as well as Sārvabhauma Bhaṭṭācārya and Vidyā-vācaspati, and He praised Murāri Gupta for his firm faith in the lotus feet of Lord Rāmacandra. Considering the humble prayer of Vāsudeva Datta, He established that Lord Śrī Kṛṣṇa is qualified to deliver all the conditioned souls.
(Sri Caitanya Caritamrta------2:15-------summary).

The word prabhu, or master, indicates that the Lord is to be continuously served by His devotee. The original prabhu is the Lord, Śrī Kṛṣṇa. Nonetheless, there are many devotees attached to Lord Rāmacandra, and Murāri Gupta is a vivid example of such unalloyed devotion. He never agreed to give up Lord Rāmacandra's worship, not even upon Śrī Caitanya Mahāprabhu's request. Such is the chastity of devotional service.
(Sri Caitanya Caritamrta------1:15:154-------purport).