According to Brahma-vaivarta Purāṇa, Śrīla Śukadeva Gosvāmī was a liberated soul even within the womb of his mother. Śrīla Vyāsadeva knew that the child, after his birth, would not stay at home. Therefore he (Vyāsadeva) impressed upon him the synopsis of the Bhāgavatam so that the child could be made attached to the transcendental activities of the Lord. After his birth, the child was still more educated in the subject of the Bhāgavatam by recitation of the actual poems.
(Srimad Bhagavatam-----1:7:11-----purport).

The sages of Naimiṣāraṇya were practically sufferers from the smoke of a sacrificial fire and were doubtful about the result, but by hearing from a realized person like Sūta Gosvāmī, they were fully satisfied. In the Brahma-vaivarta Purāṇa, Viṣṇu tells Śiva that in the age of Kali, men full of anxieties of various kinds can vainly labor in fruitive activity and philosophical speculations, but when they are engaged in devotional service, the result is sure and certain, and there is no loss of energy. In other words, nothing performed for spiritual realization or for material benefit can be successful without the devotional service to the Lord.
(Srimad Bhagavatam-----1:18:12-----purport).

In Śrīmad-Bhāgavatam Lord Kapiladeva told His mother that the living entity gets a particular type of body in accordance with his work and that this body is decided upon by higher authorities. The higher authorities, as appointed by the Supreme Personality of Godhead, are Lord Brahmā and all other Prajāpatis and Manus. Thus from the beginning of creation it can be seen that the first creature is the most intelligent. It is not that so-called modern intelligence has developed by the gradual process of evolution. As stated in Brahma-vaivarta Purāṇa, there is a gradual evolutionary process, but it is not the body that is evolving. All the bodily forms are already there. It is the spiritual entity, or spiritual spark within the body, that is being promoted by the laws of nature under the supervision of superior authority. We can understand from this verse that from the very beginning of creation different varieties of living entities were existing. It is not that some of them have become extinct. Everything is there; it is due to our lack of knowledge that we cannot see things in their proper perspective.
(Srimad Bhagavatam-----4:24:73-----purport).

In the Nārada-pañcarātra it is stated by Lord Nārāyaṇa that worship of the Deity within the mind is called mānasa-pūjā, One can become free from the four miseries by this method. Sometimes worship from the mind can be independently executed. According to the instruction of Avirhotra Muni, one of the nava-yogendras, as mentioned in Śrīmad-Bhāgavatam, one may worship the Deity by chanting all the mantras. Eight kinds of Deities are mentioned in the śāstra, and the mental Deity is one of them. In this regard, the following description is given in theBrahma-vaivarta Purāṇa.
In the city of Pratiṣṭhāna-pura, long ago, there resided a brāhmaṇa who was poverty-stricken but innocent and not dissatisfied. One day he heard a discourse in an assembly of brāhmaṇas concerning how to worship the Deity in the temple. In that meeting, he also heard that the Deity may be worshiped within the mind. After this incident, the brāhmaṇa, having bathed in the Godāvarī River, began mentally worshiping the Deity. He would wash the temple within his mind, and then in his imagination he would bring water from all the sacred rivers in golden and silver waterpots. He collected all kinds of valuable paraphernalia for worship, and he worshiped the Deity very gorgeously, beginning from bathing the Deity and ending with offering ārati. Thus he felt great happiness.
(Srimad Bhagavatam-----7:5:23-24-----purport).

Offering oblations to the forefathers in the ceremony known as śrāddha is also a kind of yajña. In this yajña, flesh obtained from the forest by hunting could be offered. However, in the present age, Kali-yuga, this kind of offering is forbidden. Quoting from the Brahma-vaivarta Purāṇa, Śrī Caitanya Mahāprabhu said:
aśvamedhaṁ gavālambhaṁ
sannyāsaṁ pala-paitṛkam
devareṇa sutotpattiṁ
kalau pañca vivarjayet
(CC.1:17:164)
"In this age of Kali, five acts are forbidden: the offering of a horse in sacrifice, the offering of a cow in sacrifice, the acceptance of the order of sannyāsa, the offering of oblations of flesh to the forefathers, and a man's begetting children in his brother's wife."
(Srimad Bhagavatam-----9:6:7-----purport).

In the Brahma-vaivarta Purāṇa it is said that one who observes fasting on Ekādaśī day is freed from all kinds of reactions to sinful activities and advances in pious life. The basic principle is not just to fast, but to increase one's faith and love for Govinda, or Kṛṣṇa. The real reason for observing fasting on Ekādaśī is to minimize the demands of the body and to engage our time in the service of the Lord by chanting or performing similar service. The best thing to do on fasting days is to remember the pastimes of Govinda and to hear His holy name constantly.
(Nectar of Devotion).

In some of the Purāṇas the evidence is given that if someone is simply meditating on devotional activities, he has achieved the desired result and has seen face to face the Supreme Personality of Godhead. In this connection, there is a story in the Brahma-vaivarta Purāṇa that in the city of Pratiṣṭhānapura in South India there was once a brāhmaṇa who was not very well-to-do, but who was nevertheless satisfied in himself, thinking that it was because of his past misdeeds and by the desire of Kṛṣṇa that he did not get sufficient money and opulence. So he was not at all sorry for his poor material position, and he used to live very peacefully. He was very openhearted, and sometimes he went to hear some lectures delivered by great realized souls. At one such meeting, while he was very faithfully hearing about Vaiṣṇava activities, he was informed that these activities can be performed even by meditation. In other words, if a person is unable to actually perform Vaiṣṇava activities physically, he can meditate upon the Vaiṣṇava activities and thereby acquire all of the same results. Because the brāhmaṇa was not very well-to-do financially, he decided that he would simply meditate on grand, royal devotional activities.
(Nectar of Devotion).