This verse is from the Bhakti-rasāmṛta-sindhu (1.2.278) of Śrīla Rūpa Gosvāmī, who further discusses this same topic in his Laghu-bhāgavatāmṛta (Pūrva 5.41). There he refers to the Viṣṇu Purāṇa (4.15.1), where Maitreya Muni asked Parāśara, in regard to Jaya and Vijaya, how it was that Hiraṇyakaśipu next became Rāvaṇa and enjoyed more material happiness than the demigods but did not attain salvation, although when he became Śiśupāla, quarreled with Kṛṣṇa and was killed, he attained salvation and merged into the body of Lord Kṛṣṇa. Parāśara replied that Hiraṇyakaśipu failed to recognize Lord Nṛsiṁha-deva as Lord Viṣṇu. He thought that Nṛsiṁha-deva was some living entity who had acquired such opulence by various pious activities. Being overcome by the mode of passion, he considered Lord Nṛsiṁha-deva an ordinary living entity, not understanding His form. Nevertheless, because Hiraṇyakaśipu was killed by the hands of Lord Nṛsiṁha-deva, in his next life he became Rāvaṇa and had proprietorship of unlimited opulence.
(Sri Caitanya Caritamrta-----1:5:36-----purport).

This is a verse quoted from the Bhakti-rasāmṛta-sindhu (1.2.239) in connection with practical devotional service. Generally people in their conditioned life engage in the pleasure of society, friendship and love. This so-called love is lust, not love. But people are satisfied with such a false understanding of love. Vidyāpati, a great and learned poet of Mithilā, has said that the pleasure derived from friendship, society and family life in the material world is like a drop of water, but our hearts desire pleasure like an ocean. Thus the heart is compared to a desert of material existence that requires the water of an ocean of pleasure to satisfy its dryness. If there is a drop of water in the desert, one may indeed say that it is water, but such a minute quantity of water has no value. Similarly, in this material world no one is satisfied in the dealings of society, friendship and love. Therefore if one wants to derive real pleasure within his heart, he must seek the lotus feet of Govinda. In this verse Rūpa Gosvāmī indicates that if one wants to be satisfied in the pleasure of society, friendship and love, he need not seek shelter at the lotus feet of Govinda, for if one takes shelter under His lotus feet he will forget that minute quantity of so-called pleasure. One who is not satisfied with that so-called pleasure may seek the lotus feet of Govinda, who stands on the shore of the Yamunā at Keśītīrtha, or Keśīghāṭa, in Vṛndāvana and attracts all the gopīs to His transcendental loving service.
(Sri Caitanya Caritamrta-----1:5:224-----purport).

The Bhakti-rasāmṛta-sindhu of Rūpa Gosvāmī explains the superexcellent quality of devotional service as follows:
brahmānando bhaved eṣa cet parārdha-guṇī-kṛtaḥ
naiti bhakti-sukhāmbhodheḥ paramāṇu-tulām api
"If multiplied billions of times, the transcendental pleasure derived from impersonal Brahman realization still could not compare to even an atomic portion of the ocean of bhakti, or transcendental service." (B.r.s. 1.1.38) Similarly, the Bhāvārtha-dīpikā states:

tvat-kathāmṛta-pāthodhau viharanto mahā-mudaḥ
kurvanti kṛtinaḥ kecic catur-vargaṁ tṛṇopamam
"For those who take pleasure in the transcendental topics of the Supreme Personality of Godhead, the four progressive realizations of religiosity, economic development, sense gratification and liberation, all combined together, cannot compare, any more than a straw could, to the happiness derived from hearing about the transcendental activities of the Lord."

(Sri Caitanya Caritamrta-----1:6:42-----purport).

Śrī Caitanya Mahāprabhu was an ideal ācārya. An ācārya is an ideal teacher who knows the purport of the revealed scriptures, behaves exactly according to their injunctions and teaches his students to adopt these principles also. As an ideal ācārya, Śrī Caitanya Mahāprabhu devised ways to capture all kinds of atheists and materialists. Every ācārya has a specific means of propagating his spiritual movement with the aim of bringing men to Kṛṣṇa consciousness. Therefore, the method of one ācārya may be different from that of another, but the ultimate goal is never neglected. Śrīla Rūpa Gosvāmī recommends:
tasmāt kenāpy upāyena manaḥ kṛṣṇe niveśayet
sarve vidhi-niṣedhā syur etayor eva kiṅkarāḥ
(Bhakti-rasāmṛta-sindhu 1.2.4) (S.B.7:1:32)

An ācārya should devise a means by which people may somehow or other come to Kṛṣṇa consciousness. First they should become Kṛṣṇa conscious, and all the prescribed rules and regulations may later gradually be introduced. In our Kṛṣṇa consciousness movement we follow this policy of Lord Śrī Caitanya Mahāprabhu. For example, since boys and girls in the Western countries freely intermingle, special concessions regarding their customs and habits are necessary to bring them to Kṛṣṇa consciousness. The ācārya must devise a means to bring them to devotional service. Therefore, although I am a sannyāsī I sometimes take part in getting boys and girls married, although in the history of sannyāsa no sannyāsī has personally taken part in marrying his disciples.

(Sri Caitanya Caritamrta-----1:7:37-----purport).

One who is not very expert in preaching may chant in a secluded place, avoiding bad association, but for one who is actually advanced, preaching and meeting people who are not engaged in devotional service are not disadvantages. A devotee gives the nondevotees his association but is not affected by their misbehavior. Thus by the activities of a pure devotee even those who are bereft of love of Godhead get a chance to become devotees of the Lord one day. In this connection Śrīla Bhaktisiddhānta Sarasvatī Ṭhākura advises that one discuss the verse in Śrīmad-Bhāgavatam beginning naitat samācarej jātu manasāpi hy anīśvaraḥ (10.33.30), and the following verse in Bhakti-rasāmṛta-sindhu (1.2.255):
anāsaktasya viṣayān yathārham upayuñjataḥ
nirbandhaḥ kṛṣṇa-sambandhe yuktaṁ vairāgyam ucyate
One should not imitate the activities of great personalities. One should be detached from material enjoyment and should accept everything in connection with Kṛṣṇa's service.

(Sri Caitanya Caritamrta-----1:7:92-----purport).

In the Bhakti-rasāmṛta-sindhu (1.1.38) it is stated:
brahmānando bhaved eṣa cet parārdha-guṇī-kṛtaḥ
naiti bhakti-sukhāmbhodheḥ paramāṇu-tulām api
"If brahmānanda, the transcendental bliss derived from understanding impersonal Brahman, were multiplied a million times, such a quantity of brahmānanda could not compare with even an atomic portion of the pleasure relished in pure devotional service."

(Sri Caitanya Caritamrta-----1:7:97-----purport).

“With one's materially contaminated senses one cannot understand the Supreme Personality of Godhead or His name, form, qualities or paraphernalia, but if one renders service unto Him, the Lord reveals Himself.” (Bhakti-rasāmṛta-sindhu 1.2.234) Here one can see the effect of the Māyāvādī sannyāsīs' service toward Nārāyaṇa. Because the Māyāvādīs offered a little respect to Śrī Caitanya Mahāprabhu and because they were pious and actually followed the austere rules and regulations of sannyāsa, they had some understanding of Vedānta philosophy, and by the grace of Lord Caitanya Mahāprabhu they could appreciate that He was none other than the Supreme Personality of Godhead, who is endowed with all six opulences. One of these opulences is His beauty. By His extraordinarily beautiful bodily features, the Māyāvādī sannyāsīs recognized Śrī Caitanya Mahāprabhu as Nārāyaṇa Himself. He was not a farcical Nārāyaṇa like the daridra-nārāyaṇas invented by so-called sannyāsīs.

(Sri Caitanya Caritamrta-----1:7:104-----purport).

One who chants in that spirit, without offenses, is certainly elevated to the platform of understanding that the holy name and the Personality of Godhead are identical. To associate with the holy name and chant the holy name is to associate with the Personality of Godhead directly. In the Bhakti-rasāmṛta-sindhu it is clearly said, sevonmukhe hi jihvādau svayam eva sphuraty adaḥ (Brs. 1.2.234). The holy name becomes manifest when one engages in the service of the holy name. This service in a submissive attitude begins with one's tongue. Sevonmukhe hi jihvādau: One must engage his tongue in the service of the holy name. Our Kṛṣṇa consciousness movement is based on this principle. We try to engage all the members of the Kṛṣṇa consciousness movement in the service of the holy name. Since the holy name and Kṛṣṇa are nondifferent, the members of the Kṛṣṇa consciousness movement not only chant the holy name of the Lord offenselessly, but also do not allow their tongues to eat anything that is not first offered to the Supreme Personality of Godhead.

(Sri Caitanya Caritamrta-----1:8:16-----purport).

These ślokas are to be discussed. Their purport is that one cannot obtain kṛṣṇa-bhakti, or the devotional service of the Lord, by official execution of the Vedic rituals. One has to approach a pure devotee. Narottama dāsa Ṭhākura sings, chāḍiyā vaiṣṇava-sevā nistāra pāyeche kebā: "Who has been elevated without rendering service to a pure Vaiṣṇava?" It is the statement of Prahlāda Mahārāja that unless one is able to accept the dust from the lotus feet of a pure Vaiṣṇava there is no possibility of achieving the platform of devotional service. That is the secret. The above-mentioned tantra-vacana, quoted from the Bhakti-rasāmṛta-sindhu (1.1.36), is our perfect guidance in this connection.
(Sri Caitanya Caritamrta-----1:8:17-----purport).

These bodily transformations are automatically manifested when one is actually situated in love of Godhead. One should not artificially imitate them. Our disease is desire for that which is material; even while advancing in spiritual life, we want material acclaim. One must be freed from this disease. Pure devotion must be anyābhilāṣitā-śūnyam (Bhakti-rasāmṛta-sindhu 1.1.11), without desire for anything material. Advanced devotees manifest many bodily transformations, which are symptoms of ecstasy, but one should not imitate them to achieve cheap adoration from the public. When one actually attains the advanced stage, the ecstatic symptoms will appear automatically; one does not need to imitate them.
(Sri Caitanya Caritamrta-----1:8:27-----purport).