Patanjali Yoga Sutra — bhava pratyayo videha prakṛtilayānām||1.19||भव प्रत्ययो विदेह-प्रकृतिलयानाम् ||१.१९||
In bhava pratyaya, (a transitory phase) sādhaka has ethereal or incorporeal (aśarīra) transcendental experiences and complete absorption in forces of nature, one with the primordial elements of prakṛti.
This is a transitional phase some Yogis reach in their sādhana between Sabīja and Nirbīja samādhi. Patañjali Maharṣi warns that these powers are considered to be by-products on the path of yoga and are quite misleading to the yogis. If they are carried away by these powers (siddhis) as the ultimate ones (and stop their sādhana), they fail to reach the pinnacle of yoga (Nirbīja samādhi), as this stage is not the ultimate kaivalya or emancipation.
Bhagavān calls these unfinished yogis as yogabhraṣṭas and His explanation is very interesting besides consoling the sādhakas:
पार्थ नैवेह नामुत्र विनाशस्तस्य विद्यते।
न हि कल्याणकृत्कश्चिद्दुर्गतिं तात गच्छति॥गीता ६.४०॥
pārtha naiveha nāmutra vināśastasya vidyate|
na hi kalyāṇakṛtkaścid durgatiṃ tāta gacchati||Gītā 6.40||
Yogabhraṣṭa never fails either in this world or in the nexts. One whose actions are guided by virtuosity is never destroyed.
प्राप्य पुण्यकृतां लोकानुषित्वा शाश्वतीः समाः।
शुचीनां श्रीमतां गेहे योगभ्रष्टोऽभिजायते॥गीता ६.४१॥
prāpya puṇyakṛtāṃ lokānuṣitvā śāśvatīḥ samāḥ|
śucīnāṃ śrīmatāṃ gehe yogabhraṣṭo’bhijāyate||Gītā 6.41||
This yogabhraṣṭa reaches puṇya lokās (like svarga: Heaven) and lives there for many years (till his puṇya phala is exhausted). Then takes a rebirth in an untainted and wealthy family.
अथवा योगिनामेव कुले भवति धीमताम्।
एतद्धि दुर्लभतरं लोके जन्म यदीदृशम्॥गीता ६.४२॥
athavā yogināmeva kule bhavati dhīmatām.
etaddhi durlabhataraṁ loke janma yadīdr̥śam ||Gītā 6.42||
Or he may get his rebirth in a dynasty of wise and yogis. Even this kind of birth is considered to be exceptionally hard to get.
According to this explanation, like a commercial entity moving to new financial year by carrying forward the credit and debit balances of every account of the previous financial year, we also carry forward the balances of puṇya and pāpa to the next birth; and an unfinished yogi gets rebirth in an environment wherein it is very conducive for resumption of his sādhana. Does it mean that I can take an excuse under this pretext saying that ‘I am not making any spiritual sādhana because my milieu is not favourable?’ mātā amṛtānandamayi’s childhood days were real eye-openers for any sādhakas. She was compelled by her parents to say good-bye to her education in her childhood days. The entire responsibility of household work was imposed on her. Though she was in her teens, she had to get up by 3.00 AM and start the day’s work. Here is a list of duties she had to execute. Imagine a typical Indian village — milking the cows, maintenance of cow-shed and poultry, turn out fiber from bark of coconut, sweeping interiors of the house and the courtyard, bringing drinking water from a distant well, cleaning the vessels, cooking for the family, lunch-boxes for her brothers and sisters, cleaning the clothes of all the family members, etc. This would be completed before 4 PM. Then the sisters and brothers would come from schools. Then her second innings starts — prepare evening snacks and coffee to all, prepare dinner, serve to all, cleaning the vessels, etc. But all through, she was in ‘Śrīkr̥ṣṇabhāva’. By 11 PM, she would complete the day’s work! She would say to herself — ‘Thank God, at last, I got a chance to meditate or sing the glories of Bhagavān’. Hence, the spiritual sādhana starts at 11 PM! In what way her surrounding was conducive for spiritual sādhana? But she achieved what others could not even dream of! She is one of the greatest spiritual leaders India has ever produced!
तत्र तं बुद्धिसंयोगं लभते पौर्वदेहिकम्।
यतते च ततो भूयः संसिद्धौ कुरुनन्दन॥गीता ६.४३॥
tatra taṁ buddhisaṁyogaṁ labhate paurvadehikam.
yatate ca tato bhūyaḥ saṁsiddhau kurunandana ||Gītā 6.43||
On his reincarnation, this unfinished Yogi would get the yogic saṃskārās of his previous birth easily and tries harder to get Kaivalya (Thus, Yogi’s any kind of spiritual sādhana will never go in vain).
brahmasūtras say, (Verse 3.3.32) — ‘There will be corporeal existence for those whose mission remains unfulfilled’. There are some instances of great ṛṣis taking embodied existence even after the attainment of brahmajñāna. The reason could be unfulfillment of their mission — say, brahmasūtras. Sanatkumāra was born as Skanda, Bhagavān takes different incarnations for the upliftment of Dharma (Righteousness). Thus, these unique cases are outside of the purview of the above-said explanation. We cannot say that these yogis (and Bhagavān) are taking rebirths as they remained unfulfilled in their yogasādhana (or they are fallen yogis).