Srimad Bhagavatam Canto 08, Chapter 03, Text 11

SB 8.3.11

sattvena pratilabhyaya
 naiskarmyena vipascita
namah kaivalya-nathaya
 nirvana-sukha-samvide
 
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada: 
 
The Supreme Personality of Godhead is realized by pure devotees who act in the transcendental existence of bhakti-yoga. He is the bestower of uncontaminated happiness and is the master of the transcendental world. Therefore I offer my respect unto Him.
 
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada: 
 
As stated in Bhagavad-gita, the Supreme Personality of Godhead can be understood only by devotional service. Bhaktya mam abhijanati yavan yas casmi tattvatah. If one wants to know the Supreme Personality of Godhead in truth, one must take to the activities of devotional service. These activities are called sattva or suddha-sattva. In the material world, activities of goodness, which are symptomatic of a pure brahmana, are appreciated. But the activities of devotional service are suddha-sattva; in other words, they are on the transcendental platform. Only by devotional service can one understand the Supreme.
 
Devotional service is called naiskarmya. Mere negation of material activity will not endure. Naiskarmyam apy acyuta-bhava-varjitam. Unless one performs activities with reference to Krsna consciousness, cessation of material activities will not be helpful. In hopes of achieving naiskarmya, freedom from material action, many highly elevated sannyasis stopped their activities, yet they failed and returned to the material platform to act as materialistic persons. But once one is engaged in the spiritual activities of bhakti-yoga, one does not fall down. Our Krsna consciousness movement is therefore an attempt to engage everyone always in spiritual activity, by which one becomes transcendental to material actions. The spiritual activities of bhakti-marga — sravanam kirtanam visnoh smaranam pada-sevanam — lead one to understand the Supreme Personality of Godhead. Therefore, as stated here, sattvena pratilabhyaya naiskarmyena vipascita: “The Supreme Personality of Godhead is realized by pure devotees who act in the transcendental existence of bhakti-yoga.”
 
The Gopala-tapani Upanisad (15) says, bhaktir asya bhajanam tad ihamutropadhi-nairasyenaivamusmin manasah kalpanam etad eva ca naiskarmyam. This is a definition of naiskarmya. One acts in naiskarmya when he fully engages in Krsna conscious activities without material desires to enjoy, either here or in the upper planetary systems, in the present life or in a future life (iha-amutra). Anyabhilasita-sunyam. When one is freed from all contamination and he acts in devotional service under the direction of the spiritual master, one is on the platform of naiskarma. By such transcendental devotional service, the Lord is served. I offer my respectful obeisances unto Him.
Srimad Bhagavatam Canto 08, Chapter 03, Text 10
Srimad Bhagavatam Canto 08, Chapter 03, Text 12