In Bhagavad-gītā, all the yoga systems—karma-yoga, jñāna-yoga and bhakti-yoga—are explained. Kṛṣṇa is the master of all such mysticism. It is to be understood, however, that as Arjuna was fortunate enough to understand Kṛṣṇa directly, so, by the grace of Vyāsa, Sañjaya was also able to hear Kṛṣṇa directly. Actually there is no difference between hearing directly from Kṛṣṇa and hearing directly from Kṛṣṇa via a bona fide spiritual master like Vyāsa. The spiritual master is the representative of Vyāsadeva also. Therefore, according to the Vedic system, on the birthday of the spiritual master the disciples conduct the ceremony called Vyāsa-pūjā.
(BHAGAVAD-GITA------18:75--------PURPORT).

In the beginning of the first half of Brahmā's life, there was a millennium called Brāhma-kalpa, wherein Lord Brahmā appeared. The birth of the Vedas was simultaneous with Brahmā's birth. According to Padma Purāṇa (Prabhāsa-khaṇḍa), in thirty days of Brahmā many kalpas take place, such as the Varāha-kalpa and Pitṛ-kalpa. Thirty days make one month of Brahmā, beginning from the full moon to the disappearance of the moon. Twelve such months complete one year, and fifty years complete one parārdha, or one half the duration of the life of Brahmā. The Śveta-varāha appearance of the Lord is the first birthday of Brahmā. The birth date of Brahmā is in the month of March, according to Hindu astronomical calculation. This statement is reproduced from the explanation of Śrīla Viśvanātha Cakravartī Ṭhākura.
(SRIMAD BHAGAVATAM--------3:11:35--------TRANSLATION AND PURPORT).

This devotional service has to be performed strongly in perfect knowledge and with transcendental vision. One must be strongly renounced and must engage in austerity and perform mystic yoga in order to be firmly fixed in self-absorption. Devotional service in Kṛṣṇa consciousness cannot be performed blindly due to material emotion or mental concoction. It is specifically mentioned here that one has to perform devotional service in full knowledge by visualizing the Absolute Truth. We can understand about the Absolute Truth by evolving transcendental knowledge, and the result of such transcendental knowledge will be manifested by renunciation. That renunciation is not temporary or artificial, but is very strong. It is said that development of Kṛṣṇa consciousness is exhibited by proportionate material detachment, or vairāgya. If one does not separate himself from material enjoyment, it is to be understood that he is not advancing in Kṛṣṇa consciousness. Renunciation in Kṛṣṇa consciousness is so strong that it cannot be deviated by any attractive illusion. One has to perform devotional service in full tapasya, austerity. One should fast on the two Ekādaśī days, which fall on the eleventh day of the waxing and waning moon, and on the birthdays of Lord Kṛṣṇa, Lord Rāma and Caitanya Mahāprabhu. There are many such fasting days. Yogena means "by controlling the senses and mind." Yoga indriya-saṁyamaḥ. Yogena implies that one is seriously absorbed in the self and is able, by development of knowledge, to understand his constitutional position in relationship with the Superself. In this way one becomes fixed in devotional service, and his faith cannot be shaken by any material allurement.
(SRIMAD BHAGAVATAM--------3:27:22--------TRANSLATION AND PURPORT).

O King Yudhiṣṭhira, at the time prescribed for reformatory ritualistic ceremonies for one's self, one's wife or one's children, or during funeral ceremonies and annual death ceremonies, one must perform the auspicious ceremonies mentioned above in order to flourish in fruitive activities. The Vedas recommend many ritualistic ceremonies to be performed with one's wife, on the birthdays of one's children, or during funeral ceremonies, and there are also personal reformatory methods like initiation. These must be observed according to time and circumstances and the directions of the śāstra. Bhagavad-gītā strongly recommends, jñātvā śāstra-vidhānoktam: everything must be performed as indicated in the śāstras. For Kali-yuga, the śāstras enjoin that saṅkīrtana-yajña be performed always: kīrtanīyaḥ sadā hariḥ [Cc. Ādi 17.31]. All the ritualistic ceremonies recommended in the śāstras must be preceded and followed by saṅkīrtana. This is the recommendation of Śrīla Jīva Gosvāmī.
(SRIMAD BHAGAVATAM--------7:14:26--------TRANSLATION AND PURPORT).

When the great sages saw the Lord as the brahmacārī-dwarf Vāmana, they were certainly very pleased. Thus they placed before them Kaśyapa Muni, the Prajāpati, and performed all the ritualistic ceremonies, such as the birthday ceremony. According to Vedic civilization, when a child is born in the family of a brāhmaṇa, the birthday ceremony, known as jāta-karma, is first performed, and then other ceremonies are also gradually performed. But when this vāmana-rūpa appeared in the form of a vaṭu, or brahmacārī, His sacred thread ceremony was also performed immediately.
(SRIMAD BHAGAVATAM--------8:18:13--------TRANSLATION AND PURPORT).

There are three kinds of ceremonies—specifically, ceremonies to please the Supreme Personality of Godhead or the demigods, those performed for social celebrations like marriages and birthdays, and those meant to please the forefathers, like the śrāddha ceremony. In all these ceremonies, large amounts of money are spent for various activities, but here it is suggested that if along with this there is recitation of the wonderful activities of Vāmanadeva, certainly the ceremony will be carried out successfully and will be free of all discrepancies.
(SRIMAD BHAGAVATAM--------8:23:31-------PURPORT).

Mother Yaśodā further told Kṛṣṇa: My dear son, because of playing all day, Your body has become covered with dust and sand. Therefore, come back, take Your bath and cleanse Yourself. Today the moon is conjoined with the auspicious star of Your birth. Therefore, be pure and give cows in charity to the brāhmaṇas. It is a custom of Vedic culture that whenever there is any auspicious ceremony, one should give valuable cows in charity to the brāhmaṇas. Therefore mother Yaśodā requested Kṛṣṇa, "Instead of being enthusiastic in playing, now please come and be enthusiastic in charity." Yajña-dāna-tapaḥ-karma na tyājyaṁ kāryam eva tat. As advised in Bhagavad-gītā (18.5), sacrifice, charity and austerity should never be given up. Yajño dānaṁ tapaś caiva pāvanāni manīṣiṇām: even if one is very much advanced in spiritual life, one should not give up these three duties. To observe one's birthday ceremony, one should do something in terms of one of these three items (yajña, dāna or tapaḥ), or all of them together.
(SRIMAD BHAGAVATAM--------8:11:18--------TRANSLATION AND PURPORT).

On the day when Lord Brahmā had first come, Baladeva could not go with Kṛṣṇa and the cowherd boys, for it was His birthday, and His mother had kept Him back for the proper ceremonial bath, called śāntika-snāna. Therefore Lord Baladeva was not taken by Brahmā at that time. Now, one year later, Brahmā returned, and because he returned on exactly the same day, Baladeva was again kept at home for His birthday.
(SRIMAD BHAGAVATAM--------10:13:40-------PURPORT).

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