CC Ādi 13.65

sarva-śāstre kahe kṛṣṇa-bhaktira vyākhyāna
jñāna, yoga, tapo-dharma nāhi māne āna
Word for word: 
sarva-śāstre — in all revealed scriptures; kahe — says; kṛṣṇa-bhaktira — of devotional service to Lord Kṛṣṇa; vyākhyāna — explanation; jñāna — philosophical speculation; yoga — mystic haṭha-yoga; tapas — austerities; dharma — religious procedures; nāhi — does not; māne — accept; āna — other.
Translation: 
In all the revealed scriptures of Vedic culture, devotional service to Lord Kṛṣṇa is explained throughout. Therefore devotees of Lord Kṛṣṇa do not recognize the processes of philosophical speculation, mystic yoga, unnecessary austerity and so-called religious rituals. They do not accept any process but devotional service.
Purport: 

Our Kṛṣṇa consciousness movement follows this principle. We do not recognize any method for spiritual realization other than Kṛṣṇa consciousness, devotional service. Sometimes we are criticized by groups following jñāna, yoga, tapas or dharma, but fortunately we are unable to make any compromises with them. We simply stand on the platform of devotional service and preach the same principles all over the world.