Chaitanya Mahaprabhu taught Sanatan Goswami—
mane nija siddha deha kariyā bhāvana

“Use the mind for contemplating your siddha deha.”
(CC 2.22.157)

The Lord similarly instructed Ramananda Raya-
siddha dehe cinti kore tāhāi sevana

“Visualize your siddha deha and mentally serve in that form.”
(CC 2.8.229)

 

Bhakti-rasāmṛta-sindhu

evā sādhaka-rūpeṇa siddha-rūpeṇa cātra hi |
tad-bhāva-lipsunā kāryā vraja-lokānusārataḥ ||295||

Translation: Following after the inhabitants of Vraja, one should perform service in one’s physical body and in one’s siddha body, with a desire for a particular bhāva.

Jīva Gosvāmī’s Commentary

sādhaka-rūpeṇa yathāvasthita-dehena | siddha-rūpeṇa antaś-cintitābhīṣṭa-tat-sevopayogi-dehena | tasya vrajasthasya nijābhīṣṭasya śrī-kṛṣṇa-preṣṭhasya yo bhāvo rati-viśeṣas tat-lipsunā | vraja-lokās tv atra kṛṣṇa-preṣṭha-janās tad-anugatāś ca tad-anusārataḥ

Sādhaka-rūpa refers to the physical body of the practitioner. Siddha-rūpa refers to the body which is suitable for one’s desired service, and which has been developed by internal meditation. One serves with a desire for the particular bhāva or rati of an associate of Kṛṣṇa situated in Vraja (tad-bhāva-lipsunā). One should follow in the footsteps of the dear associates of Kṛṣṇa in Vraja (vraja-lokā) and others loyal to them.

Viśvanātha Cakravartī Ṭhākura’s Commentary

sādhaka-rūpeṇa yathāvasthita-dehena | siddha-rūpeṇa antaś-cintitābhīṣṭa-tat-sevopayogi-dehena | tasya vrajasthasya nijābhīṣṭasya śrī-kṛṣṇasya yo bhāvo rati-viśeṣas tal-lipsunā | vraja-lokās tv atra kṛṣṇa-preṣṭha-janā śrī-rādhā-lalitā-viśākhā-śrī-rūpa-mañjary-ādyās tad-anugatāḥ śrī-rūpa-sanātana-gosvāmi-prabhṛtayaś ca teṣām anusārataḥ | tathā ca, siddha-rūpeṇa mānasī-sevā śrī-rādhā-lalitā-viśākhā-śrī-rūpa-mañjary-ādīnāṁ anusāreṇa kartavyā | sādhaka-rūpeṇa kāyiky-ādi-sevā tu śrī-rūpa-sanātanādi-vraja-vāsi-janānām anusāreṇa kartavyety arthaḥ | etena vraja-loka-padena vraja-stha-śrī-rādhā-candrāvaly-ādyā eva grāhyāḥ | tāsām anusāreṇaiva sādhaka-dehena kāyiky-ādi-sevāpi kartavyā | evaṁ sati tābhir guru-pādāśrayaṇaikādaśī-vrata-śālagrāma-tulasī-sevādayo na kṛtāḥ | tad-anugatair asmābhir api na kartavyā ity ādhunika-sauramya-matam api nirastam | ataeva śrī-jīva-gosvāmi-caraṇair apy asya granthasya ṭīkāyāṁ durgama-saṅgamanī-nāmnyāṁ tathaivoktam | tad yathā— vraja-lokās tv atra kṛṣṇa-preṣṭha-janās tad-anugatāś ca tad-anusārataḥ

One performs service with sādhaka-rūpa—the present body—and with the siddha-rūpa—the body which is suitable for serving Vraja Kṛṣṇa in the particular type of rati or bhāva one desires, and which is meditated upon (antaś-cintitābhīṣṭa) through inner contemplation with a desire for a particular rati directed to one’s beloved Kṛṣṇa situated in Vṛndāvana (tad–bhāva-lipsunā).

One should follow after the dear devotees of Kṛṣṇa such as Rādhā, Lalitā, Viśākhā, Śrī Rūpa-mañjarī and those following after them—persons such as Śrī Rūpa and Sanātana Gosvāmīs (vraja-lokānuṣārataḥ).
Accordingly, one should perform mental service in one’s siddha-rūpa, following after the examples of Śrī Rādhā, Lalitā, Viśākhā, Śrī Rūpa-mañjarī and others.
In one’s physical body, one should perform services using one’s body, following after persons such as Śrī Rūpa and Sanātana Gosvāmīs situated in Vraja.
By the word vraja-lokā, one should understand persons situated in Vraja — Rādhā, Candrāvalī and others. Following after them, one should perform service using one’s physical body also.

 

This verse in PRACTICE:

yugala caraṇa sevi,        nirantara ei bhāvi,
anurāgī thākibo sadāya.
sādhana bhāvibo yāhā,       siddha-dehe pābo tāhā
rāga pathera ei se upāya (55)

“I will always think of the devotional service of the lotus-feet of the Divine Pair, and I will always remain attached to that. Whatever I think of during my spiritual practice I will attain in my siddha deha when I reach perfection. This is the means of rāga bhakti.”

sādhane ye dhana cāi,           siddha dehe tāhā pāi,
pakkāpakka mātra se vicāra
apakke sādhana rīti,         pākile se prema-bhakti,
bhakati lakṣaṇa tattva sāra (56)

“The treasure I desire as a practitioner I will get when I attain my spiritual body; it’s just a question of being ripe or unripe. The ripe stage is the stage of pure loving devotion and the unripe stage is the stage of practice. That is the essential truth about devotional principles.”
(Srila Narottama das Thakur, Prema Bhakti Chandrika)

 

Every jiva can attain perfection in whatever rasa he/she aspires for.

Mahaprabhu gave us the CHANCE to become manjaris (in MADHURYA RASA), but nobody is FORCED to do this.

Each RASA is perfect in and on its own.

If you don´t like siddha pranali, nobody forces you to receive siddha pranali.

Manjari-bhava-sadhana is a sadhana.
Siddha pranali is a legitimate process to achieve a certain goal.