Non-Vedic faiths are equivalent to atheism/agnosticism.
Non-Vedic faiths are not true religion (not at least, in the classical Gaudiya Vaishnava perspective) —
In the beginning of the 1st Chapter, Verse 1st of Siddhānta Darpaṇaḥ, Śrīla Baladeva Vidyābhūṣaṇa and his mantra-śiṣya Śrī Nanda Miśra Prabhu (the commentator) define atheism as unbelief in the Vedic scriptures and not as mere unbelief in the existence of God. So, all other heterodox religious traditions not following Vedic Dharma and who have self-confessed themselves as the non-Vedic path-treaders in their classical sectarian texts (this includes the Indigenous non-Vedic denominations like Buddhism, Jainism, Sikhism, Vira-shaivism/Lingayatism, Pashupatism/Kashmira-shaivism, Natha sect, Aghora/Vama-marga/Kapalika, non-Vedic Shaktism etc. along with all variants of perverted neo-Hinduism like the Brahma-kumaris, Nirankaris, Radhasoamis, Sai Baba, Kabirapantha, Dadupantha etc. + the non-Vedic Occidental & Mid-eastern Abrahamic denominations like Christianity, Islam, Judaism, Zoroastrianism/Baha’i etc.) are strictly and technically speaking various forms of atheism only. Why? Because, only Vedas are the eternal scriptures guiding the religion revealed by Lord Nārāyaṇa. In this perspective, if anyone claims to perform Kṛṣna-bhakti without Vedic Dharma/saṁskṛti, he is a ‘nāstika’ (atheist) or an ‘ardha-nastika’ (semi-atheist). Evidence —
“vedaṁ tad-vācyaṁ pareśañ ca durdhiyo nāstikā na manyante. kecic ca āstikābhāsāḥ saṁśrayanty ardha-kukkuṭīyam.”
“Vedas and the God who is propounded by those Vedas are not accepted by the atheists of contaminated intelligence. Some theist-like (āstika-ābhāsa or ardha-nāstika) people take shelter of the half-chicken logic (like we believe in God or His devotion but not in the Vedic scriptures’ dictums or vice versa).”
The same notion finds affirmation in the classical Sanskrit commentaries on Maharsi Badarayana Krsnadvaipayana Vedavyasa’s Brahmasutram (Vedanta-darsanam) – “iksateh na asabdam” – where ‘pradhana/material nature/prakriti has been differed between Vedic and non-Vedic categories (especially, in Śrīla Baladeva Vidyabhusana’s Govinda-bhasyam commentary on it). The Patanjala-yoga-sutra’s maxim – “isvara-pranidhanad va” has been interpreted in the same light to distinguish between the Vedic and non-Vedic concepts of ‘isvara/God’ – thus holding non-Vedic concepts of God on par with atheism or nastikya-vada.
Link — http://wp.me/p4hS71-Iv
— Gurupadacarya Svami
(BRVF — Anand, Gujarat, Bharata & Lodi, CA, USA)