Srila Raghunatha dasa Gosvami has said that if we want to do bhakti, then we must respect all Vaisnavas, gurus, those who live in Vrndavana-dhama, even those brahmanas who are not pure devotees, and even those of other sampradayas:
gurau gosthe gosthalayisu sujane bhusura-gane
sva-mantre sri-namni vraja-nava-yuva-dvandva-sarane
sada dambham hitva kuru ratim apurvam atitaram
aye svantar bhratas catubhir abhiyace dhrta-padah
“O my dear brother, my foolish mind, taking hold of your feet, I humbly pray to you with sweet words. Please give up all pride and quickly develop deep, loving attachment for the spiritual master, Sri Vraja-dhama, the residents of Vraja, the Vaisnavas, the brahmanas, your diksa-mantras, the holy names of the Supreme Lord, and the shelter of Sri Sri Radha-Krsna, the eternally youthful Divine Couple of Vraja.” (Sri Manah-siksa, Verse 1)
We must obey these principles. These principles are of Caitanya Mahaprabhu, our guru-parampara, and Srila Bhaktivedanta Swami Maharaja. He has never said to disrespect any Vaisnava. If we want bhakti, it is imperative that we give respect to Vaisnavas.
Srila Krsnadasa Gosvami Maharaja has said that Gurudeva is also in the category of Vaisnava. Srila Rupa Gosvami is our siksa-guru, Krsna is our siksa-guru, Caitanya Mahaprabhu is our siksa-guru, and Nityananda Prabhu is our siksa-guru. Siksa-guru is not less than diksa-guru. Try to understand all these facts. Diksa-guru is not less than siksa-guru and siksa-guru is not less than diksa-guru. Both are equal if they are qualified. If they are not qualified, then they are not guru.
May 5, 1996 in Holland