The impulse of a saintly person is to be engaged in the study of the Vedas, especially the Upaniṣadic portions, to always live in a place where there is no disturbance from the common people, to always think of the eternal form of Kṛṣṇa, to be ready to consider and understand the absolute truth, to always be prominent in exhibiting knowledge, to see the Supreme Lord in His universal form (viśva-rūpa), to associate always with learned devotees and to discuss the conclusion of the Vedas with similarly elevated persons. All of these qualifications of a saintly person serve to raise him to the status of śānta-rasa.
In the Bhakti-rasāmṛta-sindhu it is stated that all those who attended the pious meeting held by Lord Brahmā for the study of Vedic literature like the Upaniṣads became overwhelmed with ecstatic love for Kṛṣṇa, the chief of the Yadu dynasty. Actually, the result of studying the Upaniṣads is to understand the Supreme Personality of Godhead. Negation of material existence is only one of the subjects of the Upaniṣads. The next subject concerns becoming situated in the impersonal realization. And then, after penetrating through the impersonal Brahman, when one comes to the platform of associating with the Supreme Personality of Godhead, one reaches the ultimate goal in studying the Upaniṣads.
Those who are situated on the platform of śānta-rasa get their impetus for advancement in devotional service by smelling the tulasī offered at the lotus feet of the Lord, by hearing the sound of His conchshell, by seeing a sanctified place in some mountain or hill, by observing a forest like the ones in Vṛndāvana, by going to a place of pilgrimage, by visiting the course of the Ganges River, by being victorious over the dictations of bodily demands (i.e., eating, sleeping, mating and defending), by understanding the devastation of eternal time, and by constantly associating with devotees engaged in Kṛṣṇa consciousness. All these different items are favorable in elevating saintly persons situated in śānta-rasa to the advanced stage of devotional service.
In the Third Canto, 15th Chapter, 43rd verse of Śrīmad-Bhāgavatam there is a statement by the four saintly persons known as Catuḥsana, headed by Sanaka-kumāra. They went to visit the Lord of Vaikuṇṭha-loka in the spiritual sky, and when they bowed down before the Lord, the aroma of the tulasī, mixed with saffron, entered their nostrils and immediately attracted their minds. Although these four saintly persons were always absorbed in the thought of impersonal Brahman, from association with the Lord and from smelling the tulasī leaves, the hairs on their bodies immediately stood up. This shows that even a person who is situated in Brahman realization, if he is put into association with devotees in pure devotional service, will immediately become attracted to the personal feature of the Lord.
There are certain symptoms of great sages who are situated in śānta-rasa devotional service, and these symptoms are exhibited as follows: they concentrate their eyesight on the tip of the nose, and they behave just like an avadhūta. Avadhūta means a highly elevated mystic who does not care for any social, religious or Vedic conventions. Another symptom is that such persons are very careful to step forward when giving speeches. When they speak, they join together the forefinger and thumb. (This is called the jñāna-mudrā position.) They are not against the atheists, nor are they particularly inclined to the devotees. Such persons give stress to liberation and detachment from the materialistic way of life. They are always neutral and have no affection for nor misidentification with anything material. They are always grave, but fully absorbed in thoughts of the Supreme Personality of Godhead. These uncommon features develop in devotees who are situated in śānta-rasa.
Regarding concentration of the eyesight on the tip of the nose, there is a statement in the Bhakti-rasāmṛta-sindhu by a devotee who observed this being performed by a yogī. He remarked, "This great sage is concentrating his eyesight on the tip of his nose, and from this it appears that he has already realized the eternal form of the Lord within himself.