1094
Śrīmad-Bhāgavatam
[Canto 4, Ch. 24]
Thus if one desires to enter into the spiritual world, he must try to understand the Supreme Personality of Godhead by practicing  bhakti-yoga . Simply by practicing  bhakti-yoga  one can understand the Supreme Lord in truth, but without such understanding, one cannot enter the spiritual kingdom. One may be elevated to the heavenly planets or may realize himself as Brahman ( aham brahmāsmi ), but that is not the end of realization. One must realize the position of the Supreme Personality of Godhead by  bhakti-yoga ; then real perfection of life is attained.
TEXT 55
तं दुराराध्यमाराध्य सतामपि दुरापया । एकान्तभक्त्या को वाञ्छेत्पादमूलं विना बहिः॥५५॥
tam durārādhyam ārādhya satām api durāpayā ekānta-bhaktyā ko vāñchet pāda-mūlam vinā bahiḥ
tam —unto You;  durārādhyam —very difficult to worship;  ārādhya —having worshiped;  satām api —even for the most exalted persons;  durāpayā —very difficult to attain;  ekānta —pure;  bhaktyā —by devotional service;  kaḥ —who is that man;  vāñchet —should desire;  pāda-mūlam —lotus feet;  vinā —without;  bahiḥ —those who are outsiders.
TRANSLATION
My dear Lord, pure devotional service is even difficult for liberated persons to discharge, but devotional service alone can satisfy You. Who will take to other processes of self-realization if he is actually serious about the perfection of life?
PURPORT
The word  satām  refers to transcendentalists. There are three kinds of transcendentalists: the  jñānī ,  yogī  and  bhakta . Out of these three, the  bhakta  is selected as the most suitable candidate to approach the Supreme Personality of Godhead. It is emphasized herein that only one who is outside devotional service would not engage in searching for the lotus feet of the Lord. Foolish people sometimes maintain that God may be attained in any way—either by  karma-yoga ,  jñāna-yoga ,  dhyāna-yoga , etc.—but here it is clearly stated that it is impossible to obtain the mercy of the Lord by any means but  bhakti-yoga . The word  durārādhya  is especially significant.