In this page, we have presented musings which represent 'other side of coin' of certain concepts which are generally taken to [obviously] mean a specific thing.But before starting a detailed study, we will give our conclusions in brief
Lets begin our study with the analysis of anya-devatA worship, vaikunTha, parampada and param dhAma in gItA
In this article, we will cover interpretations of Anya-devata, pada and dhAma by AchArya-s of different Vaishnava sampradaya
यान्ति देवव्रता देवान् पितृ़न्यान्ति पितृव्रताः।
भूतानि यान्ति भूतेज्या यान्ति मद्याजिनोऽपि माम्।।9.25।।
yānti dēvavratā dēvān pitṛnyānti pitṛvratāḥ.
bhūtāni yānti bhūtējyā yānti madyājinō.pi mām..9.25..
English translation by Swami Gambhirananda
9.25 Votaries of the gods reach the gods; the votaries of the manes go to the manes; the worshippers of the Beings reach the Beings; and those who worship Me reach Me.
9.25 Worshippers of the gods (devata-s (deva-s) ascend and stay in deva-loka; the worshippers of the ancestors (staying on chandra-loka) go to the manes (chandra-loka); the worshippers of the Ghosts (bhUta, piSAca) reach their loka; and those who worship Me (Ishvara) reach Me.
Note: Deva-loka means heaven. Chandra means moon. Loka can be taken as kingdom. Just like there is earth kingdom, there is sun-kingdom, moon-kingdom, etc.
Sri rAmAnuja explains the meaning of the word 'vrita' mean 'will'.
The worship here refers to kAmya-karma i.e. worshipping done with some objective in mind i.e. to fulfill our desires or for peace and spiritual progress of our ancestors. There are rituals mentioned in verses which mimAmsaka-s follow. They do not consider that all actions and their fruits has to be surrendered to Ishvara. They think that veda-s give us fruits of rituals and in general veda-s give fruits of our deeds. Bhagavad Gita is the essence of Upanishads and hence it is a moksha shastra. Gita is not dharma-shastra-s which teach us religious observances, nor it is an agama, which deals with idol worship, temple construction and consecration of deities. Like the upanishads, Gita also talks about renouncing vedic rites. In this context, the verse under discussion says that instead of worshipping other Gods for personal benefits or even for universal benefit, one should worship Ishvara. It should be noted that a seeker, who has purified his mind by doing vedic rites and rituals has to drop the very karma that gave him inner purity and move ahead to Atma Jnana. Hence vedic rites and other kinds of worships are discouraged by Bhagavan fo a devotee who lives his life only and only for Ishvara and wants nothing else.
It should be noted that the verse does not contain the word 'Vaikuntha'. We have picked up this verse as this verse specifically deals with doing worship and as a merit of worship, one attains or stays in the loka of a deity worshipped. In other words, this verse talks about devata-worship and their loka-s. Kindly note that the word used by Bhagavan is not 'my loka'. Bhagavan says, those who worship me attain 'Me'. None of the acharya-s have translated the word 'me' as 'loka'. All acharya-s include Adi Shankara, four Vaishnav acharya-s, Shreedhar Svami (hid commentary is accepted by Nimbarka sampradAya) and Abhinava Gupta (Kashmir Shaivism).
It should be noted that Shiva is considered as Ishvara and not just a devata (demi-God). Hence this verse excludes Shiva / Rudra. None of the acharya-s have clarified on this verse that Ishvara (Shiva) is also anya devata in this verse. Typically, Sri Rudram is advised to be daily chanted even by the Vaishnava-s. While studying agama-s, which deal with procedures of temple worship, one school teaches both shaiva and vaishnava agama-s. According to Kanchi Paramacharya, while learning VAilhAnasa, a Vaishnava agama (other being pAncharAtra), Brahmins conducted puja in Shiva temples are are called Shivayogins. Under the same roof (ghaTikA-s, big school teaching various subjects), vaishnava and shaiva agamas were taught (Source: Guru Tradition, Page 153).
We will find that nowhere in Gita there is a description or even the mention of the word Vaikuntha. I am not aware of Upanishads, which talk about Vaikuntha, at least not the principle upanishads.
Verses containing the word 'padam' are 2.51, 8.11, 15.4, 15.5, 18.56
In BG 8.11, achArya-s explain the meaning of the word 'pada' (पद) or 'padaM' / 'pada.m (पदं).
Note: 'pada' (पद) or 'padaM' / 'pada.m (पदं) - note the difference is anusvAra (dot) above the word pada in second spelling. This is denoted in transliteration as '.m' or 'M'
Sri rAmAnuja explains us the meaning of 'pada' as, 'What is attained by the mind as its goal is called 'pada''
Sri mAdhvA explains us the meaning of 'pada' as, 'Since the aspirants attain that consciousness it is known as pada.m' and '
Full commentary of the verse is :
The ultimate goal to be attained is explained by Lord Krishna in this verse. Since the aspirants attain that consciousness it is known as padam or state and once that state is reached it is designated by the word 'visanti' meaning to enter. The Narada Purana states: That the ultimate goal to be attained is Lord Krishna is confirmed in the Vedic scriptures. Since that consciousness is achieved by the ascetics, it is known as padam.
Now begins the summation.
Brahmacarya or voluntary celibacy for spiritual purposes denotes attuning one's consciousness in full devotion to the Supreme Lord excluding everything else.
Sri Sridhara svAmI explains akshara as praNava OM.
Lord Krishna speaks this verse with a view to instruct how the preceding practice is based on the sacred syllable OM which is the most dearest and nearest  transcendental sound vibration of the Supreme Lord.
Sanskrit commentary is
'केवलादभ्यासयोगादपि प्रणवाधारमभ्यासमन्तरङ्गं विधित्सुः प्रतिजानीते -- यदक्षरमिति।' . If we split the verse we get
केवल-अभ्यासयोगः-अपि प्रणव-आधार-अभ्यास-अन्तरंग विधि-अस्तु- प्रतिजानिते यदम्-अक्षरम्-इति
 The word antaranga can be defined as antar-anga. Antar means 'inner' and anga means 'organ'. In reference to context with BG 7.8, we can take that OM is the closest to ParamAtmA. By meaning closest, it is verily the ParamAtmA. We hear the word 'antaranga-bhakta'
We all know that OM represents nirguNa brahman. Bhagvan in Gita says 'I am OM' (BG 7.8)
The purpose of commentary is to give more clarity of the verse. Here, no acharya has mentioned pada as loka or as Vaikuntha, nor do the references made to Br. Up. mention Vaikuntha. The question is why didn't they mention the word vaikuntha, refuted advaita and shaivism.
Sri Adi Sankara mentions the pada, as 'that which is the goal, is neither gross, nor subtle', indicating that Brahman is beyond description.
Sri Abhinava Gupta mentions pada as 'the goal'
Commentaries on 15.4 and 15.5 do not describe of any pada as loka, neither it mentions Shiva as anya-devata.
English translation of mAdhvAchArya, as found here, contains extra words:
...the Vedic aphorism neti neti meaning it is not this, it is not that clarifies what is the unmanifest. Realising that the Supreme Lord Krishna is the seperate and distinct from all else is what makes Him clearly superior and paramount. He is the primal Supreme Lord, the only progenitor. All created beings including Brahma, Shiva, Indra and all the 300 million demigods are nothing but emantions from Him like rays of sunlight from the sun.
However, the sanskrit commentary, as available on Gita Super Site, does not say mention the word Shiva.
Sanskrit commentary by Sri Madhvacharya
तदर्थं च तमेव प्रपद्ये प्रपद्येत। तच्चोक्तं तत्रैव "तं वै प्रपद्येत यं वै प्रपद्य न शोचति न हृष्यति न जायते न म्रियते तद्ब्रह्म मूलं तच्छित्सुः" इति।'नारायणेन दृष्टश्च प्रतिबुद्धो भवेत्पुमान्' इति च मोक्षधर्मे। छेदनोपायो ह्यत्राकाङ्क्षितः न च भगवतोऽन्यः शरण्योऽस्ति ।।15.4।।
साधनान्तरमाह -- 'निर्मानेति' ।।15.5।।
While commenting on BG 18.46, none of the acharya-s talk of vaikunTha. Sri rAmAnuja talks of 'शाश्वतं पदम् अव्ययम्' (SASvata.m padam avyayam), which could be connected with BG 15.4.
Hence we can conclude that none of the vaiSNava acharya-s say that the param pada is viShNu-loka (heavenly planet or heavenly kingdom of Lord Vishnu) which is Vaikuntha. Pada or Parampada, 'reach Me' etc has to be taken as a state of as MAdhvAchArya says 'consciousness'. Atleast this can be taken as an alternate explanation or they left gap to give room for another interpretation.
Kena Upanishad says that ...Indra excelled than other Gods as he was the first to know that 'I am Brahman' (4.2-4.3)
BG 3.35 uses the word 'to know' (GYAna chakShu means eye of knowledge, which is nothing but knowledge itself.
BG 9.11 and 9.13 also asks us to know. BG 10.2 says that even demi-gods and great sages do not know my true nature.
Ch. Up. VII-xxv-2 also uses the word 'to know'.
Nowhere it is mentioned 'to see'.
It is interesting to note that none of the acharya-s have connected with bhAgavat pUrANa (Srimad bhAgavatam).
Word 'desa' or 'desam' occurs in 8.21, 8.28, 15.6
Sri rAmAnuja and Sri mAdhva gives definition of dhAma as luminosity which means prakASa (prakash) and prakASa means Jnana (Knowledge)
Sri Ramanuja says: BG 8.21 Or the term 'dhama' may signify 'luminosity'. And luminosity connotes knowledge. The essential nature of the freed self is boundless knowledge, or supreme light, which stands in contrast to the shrunken knowledge of the self, when involved in Prakrti. The description given above is that of Kaivalya, the state of self-luminous existence as the pure self.
Sridhara svamI says
The six causative case by the word mama meaning my is used in the sense of identity as when one states Rahu's head which is all that remains of Rahu, it means only that. Therefore Lord Krishna, Himself is the paramam gatim and no other. This is the purport.
While commenting on the verse BG 8.28, none of the acharya-s have explained the meaning of 'desha' or 'deSa'
In BG 15.6 Sri rAmAnuja explains light (prakASa) i.e. Knowledge as
The supremacy of this light (i.e., individual self) consists in its capacity to illumine the light of knowledge. Knowledge alone can illuminate all things (including the light of the sun which sheds only physical light on objects.).
From the above explanation, what I have concluded is that the param pada, dhAma is light, which is knowledge, which is state of consciousness.
Lets understand the meaning of word dhAma as explained by Adi Sankara in viShNu sahasranAma bhAshya name #211 धाम (dhAma)
jyoti is called as dhAma. In mantravarNa i.e. nArAyaNa Up. 13.1 it is said 'nArAyaNa is parama jyoti' or by being the support or substratum ofall desires (kAmanA-s) bhagavAn is known as dhAma. shruti i.e. Br. Up. 2.3.6 says, 'is parama brahma and param dhAma'
In the next name $212 सत्य (satya), Adi Sankara says, ... shruti says, 'hence truth (satya) is called as parama' or is the truth of the truth hence is truth. Shruti i.e. Br. Up. 2.3.6 says, 'prANa is truth, [paramAtmAn] is the truth of this truth i.e. paramAtmAn is higher truth'