In the Brahmāṇḍa Purāṇa it is said, "A person who sees the Lord's Ratha-yātrā car festival and then stands up to receive the Lord can purge all kinds of sinful results from his body."
Following the Deity
A similar statement is there in the Bhaviṣya Purāṇa, in which it is said, "Even if born of a lowly family, a person who follows the Ratha-yātrā car when the Deities pass in front or from behind will surely be elevated to the position of achieving equal opulence with Viṣṇu."
(Nectar of Devotion).

In all festivals the Lord is seated on a car, and the car moves through different streets of the city so that people may take advantage of visiting the Lord. In theBhaviṣya Purāṇa it is said, "In such a ceremony, if even a caṇḍāla (dog-eater), simply out of curiosity, sees the Lord on the cart, he becomes counted as one of the associates of Viṣṇu."
(Nectar of Devotion).

Observing Festivals Celebrating the Lord's Activities
In the Bhaviṣya Purāṇa there is a statement about observing different ceremonies celebrating the Lord's appearance (birthday) and other transcendental activities. It is said, "My Lord Janārdana (Kṛṣṇa), please let us know the date when Your mother Devakī-devī gave birth to You. If You kindly inform us about this, then we shall observe a great celebration on this date. O killer of Keśī, we are souls one-hundred-percent surrendered unto Your lotus feet, and we wish only to please You with our ceremonies."
This statement of the Bhaviṣya Purāṇa gives evidence that by observing different functions in relationship with the Lord one is sure to become pleasing to the Lord.
(Nectar of Devotion).