Srimad-Bhagavatam: Canto 9 - Chapter 1 - Verse 67

Sanskrit:

मत्सेवया प्रतीतं ते सालोक्यादिचतुष्टयम् ।नेच्छन्ति सेवया पूर्णा: कुतोऽन्यत् कालविप्लुतम् ॥ ६७ ॥

ITRANS:

mat-sevayā pratītaṁ tesālokyādi-catuṣṭayamnecchanti sevayā pūrṇāḥkuto ’nyat kāla-viplutam

Translation:

My devotees, who are always satisfied to be engaged in My loving service, are not interested even in the four principles of liberation [sālokya, sārūpya, sāmīpya and sārṣṭi], although these are automatically achieved by their service. What then is to be said of such perishable happiness as elevation to the higher planetary systems?

Purport:

Śrīla Bilvamaṅgala Ṭhākura has estimated the value of liberation as follows: Bilvamaṅgala Ṭhākura realized that if one develops his natural devotional service to the Supreme Personality of Godhead, mukti stands before him with folded hands to offer all kinds of service. In other words, the devotee is already liberated. There is no need for him to aspire for different types of liberation. The pure devotee automatically achieves liberation, even without desiring it.