It is stated explicitly that the spiritual world is a manifestation of the Lord's internal pleasure potency, svarupa-sakti, the Lord's most powerful potency. "Whereas the material energy is conducted by the external potency, maya, the spiritual world is conducted by the internal potency, Radharani." (Elevation to KC, Ch. 5) And the residents thereof are firmly situated under the protection of that internal potency-antatanga-sakti-vilasanugrhita. (Bhagavat-sandarbha 78) This is also stated in Bhagavad-gita 9.13, daivim prakrtim asritah, that great souls are under the protection of the Lord's divine potency. Sri Jiva shows in Bhagavat-sandarbha 75-78 that the Lord's associates are within His own svarupa. They are all suddha-sattva in nature-tripadvibhuter lokastu asankhyah parikirttitah suddha-sattva-maya sarve brahmananda-sukhahvayah. Thus, to argue that His eternal associates fall implies that the Lord Himself can fall down. Srila Prabhupada states, "It is a most ludicrous argument to say that the Supreme Lord is overpowered by His own material energy." (Bhag. 3.7.9, purp.)
This is the conception of the impersonalists who think that a portion of the Lord's svarupa sakti, the Lord's most powerful sakti, can be covered by maya. Srila Sanatana Goswami states in Brhad-bhag. 2.4.183, saktya sampaditam yat tu sthiram satyam ca drsyate, that all the manifestations of the internal potency are stable and real-once one attains bhakti, it becomes part of the devotees essential nature and cannot be destroyed or reduced.
The suddha-sattva spiritual body of the eternally liberated devotee, which is composed of pure spiritual energy, must transform and become covered by matter in the form of a new subtle and gross body, if a nitya-parsada is to fall to the material world. This is again the philosophy of Mayavada. The following quote supports this:
When one goes to a transcendental planet, it is necessary to change both the finer and gross bodies, for one has to reach the spiritual sky completely in a spiritual form. (Cc. Adi-lila 5.22, purp.)
Jiva Gosvami in Krsna-sandarbha, texts 117-152, explains the eternal nature of the Lord's associates. Here the glories of the Lord's internal potency and it's infallible nature are revealed in detail. In view of these conclusive statements of Jiva Goswami it is clear that to even imply that the maya-sakti could have any influence whatsoever on a resident of Vaikuntha is tantamount to saying that the internal potency is fallible. This is the philosophy of the Mayavadis, that maya can cover brahman. Actually, it is worse than Mayavada for it suggests that not only brahman but Parabrahman may be covered by maya.
Sri Jiva states further,
The Yadavas and Vrajavasis are His eternal associates. (Krsna-sandarbha, text 153)
And in his commentary on Bhag. 3.7.37 Sri Jiva writes,
By this verse only, the eternality of the Lord's associates is conveyed.
Visvanatha Cakravarti Thakura:
This verse aims at explaining that the associates of the Lord, devotion to the Lord, and the planet of the Lord are all eternal. (Commentary on Bhag. 3.7.37)
Avidya, which is anadi, is situated on the backside of the Lord and has the nature of ignorance. She covers the knowledge of the jivas who are situated on the backside of the Lord and are non-devotees. Their non-devotion is anadi. There is no real reason or purpose for their knowledge being covered. (Bhag. 3.7.10 commentary)
It is stated in Bhag. 2.5.13 that maya never appears in front of the Lord, therefore it is apparent that those who are situated on the front side of the Lord, the pure devotees, are never effected by maya.
Srila Bhaktisiddhanta Sarasvati Thakura:
In Cit-jagat there is no ignorance whatsoever of free souls whereas in Mayik Jagat, mayik impressions of fallen fettered souls are always obscured with intervening materials. (Sri Caitanya's Teachings-Part II, Chapter One, p. 390-1)
Srila A. C. Bhaktivedanta Swami Prabhupada
The Brahma-samhita describes this supreme abode as ananda-cinmaya-rasa, a place where everything is full of spiritual bliss . . . nothing there is material . . . the manifestation there is totally of the spiritual energy. (Bg. 8.22, purp.)
Are we to suggest that the Lord's internal potency is fallible and imperfect? Many references attest to the invincibility of the Lord's internal potency-that the superior energy of the Lord (svarupa-sakti) can be overwhelmed by the inferior energy of the Lord (maya-sakti) is not supported anywhere by sastra or by any acaryas. Yet even disregarding the direct statement of the Srimad-Bhagavatam 2.9.10, that maya cannot enter the spiritual world, this theory that all jivas in the material world come by falldown from the spiritual world requires that the eternal associates of Krsna be influenced by maya in order for them to become illusioned. For "the living entity cannot be forgetful of his real identity unless influenced by the avidya potency." (Bhag. 3.7.5, purp.)
Those who adhere to the philosophy of Sankaracarya state that all the creations are maya and are therefore false, so when we allow an imperfection to enter into our description of the spiritual world, we are wide open for the impersonalists to simply state, that yes, you admit imperfection in your spiritual world; it is just like the material world, all false. Certainly it is considered an imperfection of the spiritual world that one firmly situated under the personal protection of the divine internal potency of the Lord and ecstatically engaged in the Lord's loving transcendental service can fall from that.