Attainment of Hari-Bhakti is Extremely Rare

(From "Bhakti Tattva Viveka" - click to read more from it.
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Attainment of hari-bhakti is extremely rare, sudurlabha.
Srila Rupa Goswami writes about the extreme rarity of bhakti (Bhakti-rasamrita-sindhu 1.1.35):
sadhanaughair anasangair alabhya sucirad api
harina cashv adeyeti dvidha sa syat sudurlabha
There are two reasons for hari-bhakti being so rare.
First, it cannot be achieved in spite of engaging in many varieties of sadhana for a long period of time as long as one is bereft of firm faith and unwavering persistence.
Second, Sri Hari does not easily grant His bhakti even though one may be engaged in asanga-yukta-sadhana or sadhana endowed with unflinching attachment.
The word ‘asanga’ implies expertise in bhajana.
Without expertise in bhajana, no sadhana can grant hari-bhakti.
By executing sadhana with expertise in bhajana for a long period of time and after Nama-aparadha and Vaisnava-aparadha have been dispelled, by the mercy of Bhagavan shuddha-bhakti which establishes one in knowledge of his constitutional identity arises in the heart.
jnanatah sulabha muktir bhuktir yajnadi punyatah
seyam sadhana-sahasrair hari-bhaktih sudurlabha
Bhakti-rasamrita-sindhu 1.1.36
“By the cultivation of jnana one can easily obtain mukti and by the performance of sacrifices and other pious activities one can also easily obtain bhukti, but despite performing innumerable sadhanas one cannot achieve hari-bhakti so easily.”
Bhagavan does not easily grant His bhakti, as confirmed in Srimad-Bhagavatam (5.6.18 and Bhakti-rasamrita-sindhu 1.1.37):
rajan patir gurur alam bhavatam yadunam
daivam priyah kula-patih kva ca kinkaro vah
astv evam anga bhajatam bhagavan mukundo
muktim dadati karhicit sma na bhakti-yogam
“My dear King Parikshit! Lord Mukunda Himself was the protector, guru, ishtadeva (worshipable Deity), well-wisher and kula-pati (head of the dynasty) of the Pandavas and the Yadu dynasty.
Sometimes He even became their obedient servant.
It is a matter of great fortune because Bhagavan easily grants mukti to those engaged in His bhajana, but He doesn’t easily award His prema, which is far superior to mukti.”
In his commentary to this verse, Srila Jiva Goswami comments, “tasmad asangenapi krite sadhana-bhute sakshad bhakti-yoge sati yavat phala-bhute bhakti-yoge gadhasaktir na jayate tavan na dadatity arthah”: those who engage in bhagavad-bhajana by executing the ninefold limbs of bhakti are not granted shuddha-bhakti by Bhagavan until they develop strong attachment for rati-tattva which is the fruit of the perception of one’s eternal identity.
Until that time comes, one’s bhakti remains in the form of chaya-bhakti-abhasa.(from Part 3 – "An Analysis of the Natural Attributes of Bhakti")
Another revelation, What philosophical conclusions have Acharyas preached based on Brahma-sutra?. Check out the previous page too: How many divisions does Brahma-sutra have?. You will benefit from reading the whole work: Bhakti Tattva Viveka.And now listen to this sound >>
Harih Om Tat Sat.
Natural Brotherhood (Bhaktivinoda Thakura):

"Gradually, when the offensive portions of the established religions are destroyed, there will be no more differences in the bhajana performed by the various Sampradayas nor any quarrel between them.
Then as brothers, the people of all castes and countries will spontaneously chant the Holy Names of the Supreme Lord together.
At that time, no one will hate anyone or consider others dogeaters; nor will anyone be overwhelmed by the pride of high birth.
The living entities will not forget the principle of natural brotherhood."