ShankaraDeva is The Vaishnava Saint and Acharya, Who preached in Assam (don't consuse with Shankara-Acharya, the founder of Advaita).
The Bhakati Pradip of Sankaradeva
The Bhakati Pradip of Sankaradeva is a work complete in 313 verses and deals with the sole devotion to Lord Krishna.
The facts have been taken from the Garuda Purāna which brings out its topic in the form of a discourse between Krishna and Arjuna just as the Gitā is told:
Garuda Purān Krishna-Arjuna Samvāda
Like most of Sankaradeva's writings, it is almost an original work and he writes freely, of course without departing from the main theme of his source.
The caritas refer to Bhakati Pradip as an early work of Sankaradeva.
The plot begins when for the performance of the Rājasuya sacrifice various sages assembled and had a discourse on the comparative merit of religious performances:
Yata Devarisi Rājarisi Brahmarisi:
Bhailanta ekatra sehi sabhāt harisi. 10
Yagne dāne vrate moksa kāhāro yuguti:
Keho bole mahā jnān yogat mukuti.
Keho bole sādhe gati ei Rājasui;
Angira Nārade bulilanta kichu nui. 11
Jnān karma yogak karanto mahā kasta:
Alpa chidre kare tāk tetiksane bhrasta.
Rājasuya kari yeve Brahmaloke care:
Punya ksay bhaile dunāi samsārat pare. 12
Bance Brahma lokat ācari tapa yog:
Nāhi eko sukh indriyar mātra bhog.
Māyāmay deva dharma samaste vināsi;
Āto moksa āche suni uthe mor hāsi.13
All the god-sages, king-sages and Brahma-sages gladly assembled on that occasion.
Some of them opined that sacrifices, gifts and fasting could bring about salvation.
Others said that salvation could be had by the great cult of knowledge.
Yet others maintained that only the Rājasuya could lead to final emancipation.
Hearing these arguments, the sages Angira and Nārada said that these are nothing.
Jnāna (knowledge), karma (ritual) and Yoga are beset by great hardship; moreover, these become useless on a slight fault [on the practiser?s part].
The Rājasuya may raise its performers to Brahmaloka, but when the merits are spent up, he again drops down to the world.
Besides, when by meditation etc, a person stays in the Brahmaloka, he obtains no bliss, only the gratification of the senses.
All such faiths relating to the gods are ephemeral (destructible) and full of illusions. It makes me laugh to hear that such religions can bring about salvation.
Superiority of Bhakti
Bhagavan Shree Krishna corroborated this last view:
Bolanta Kesave sunā uttar ihār:
Hauka nara yadyapi param durācār.
Moke mātra bhajay nupuji deva ān:
Tathāpi param sādhu sei mor prān. 34
Nabādhay dose tāk tejio samsay:
Satye satye dibo moksa sakhi Dhananjay.
anācāra kari aparādhi mora nuhi
ānadeva puje yito sei mora drohi. 35
Mahāmoksadātā mot pare nāhi kev:
Tathāpito teji mok puje ān dev.
yito mahāmleccha khāy kukkuraka māri
tāto kari apavitra sito ahamkāri. 36
dekhi bura diba lāge nāi tāta citra
candālaro asprisya ehise apavitra.
Mai nij pitrik karile apamān:
Brahmāndat nāi pāpi tāhār samān. 37
[Krishna said:] Hear my answer to this.
Be a person a big rogue, but if he worships Me and Me alone, and never worships other gods he must be a great saint and dear to Me as my life.
No defects can stop him, know it for certain, and I tell you most truly, O Arjuna, that I will deliver him from this world.
One cannot be sinful to Me by violating the established rules of conduct, but one becomes a sinner to me by worshipping other gods.
I am the Giver of Salvation (Moksha) and there are none of this power else than Me; if in spite of this, a person worships other gods in preference to Me, then he must be more despised than one who kills dogs to eat their flesh.
There is nothing to wonder that one who suffers the sight of such a person should immediately purify himself by diving into the water.
Such a wretch is impure and untouchable even for an outcaste; for he insults Me Who am his own Father.
There can be no sinner in this universe worse than him.
This however did not convince Arjuna who asked forthwith:
Tomāk nupuji ān deva puji
Cāndālatodhika hove;
Hena viparita kaito natu suni
Cāndālo tāka nochove. 45
I have never heard such an extraordinary thing that a person may become worse than an outcaste, rather untouchable, for even an outcaste, by worshipping other gods in preference to You.
Krishna then told Arjuna an interesting incident how an outcaste woman (Cāndālini) who was devoted to Him actually dived in the sacred Ganges hundred and eight times, and also took to what may be called ?internal washing? by reciting one thousand and one Names of Krishna in repentance, simply for talking with a Brāhmana who used to worship other gods in preference to Visnu.
Meanwhile came Nārada:
Tolanta yantrat nād amrit susvar
Āpuni gāvanta git kanthe kokilar.78
Jagat pavitra hove suni Rām vāni:
Kāstho drave atisay sila srave pāni.
Vriksasavo munjare sarir romāncit:
Ānande hiāt honta Isvar bidit. 79
In his musical instrument he raised a sweet note that showered nectar, and he himself sang with the voice of a cuckoo.
The world becomes sanctified to hear the glories of Rāma.
The wood softens and the stone melts into water. The trees blossom and the body feels a thrill of joy.
And God reveals Himself through joy in hearts.
Nārada who knew all about the outcaste woman, burst into saying:
Dhanya dhanya Cāndālini mati ye uttam:
Nedekhilo Bhakat param toka sam.
Niscay jānili tattva Krishna Devatār:
Tor darasane bhailo āmio nistār. 93
Cārio Vedar tattva tai āchā jāni.
Taisi uttam jāti tai mahā māni.
Tirthak pavitra karā āt kon citra;
Tor sanga pāile huiba jagat pavitra. 94
Glory to you, O outcaste woman. Yours is the happiest intellect.
I have never come cross a devotee equal to yourself.
You have known the real mystery of Love of Krishna.
We are also delivered from this world by your sight.
It is you who have known the real philosophy (tattva) of the four Vedas. You do really belong to the best of the castes.
You are truly worthy of respect.
What wonder is it that you can sanctify the sacred places themselves.
The world can be purfified by enjoying your company.