Day and night for the Manes, Gods and Brahma

(a) Paitra (I. 3. 21; p. 36)–

[Day and night for the manes:]

Amarakośa defines a day and night of the manes equivalent to a month of humans.

Kṣīrasvāmin explains that the dark fortnight (kṛṣṇa pakṣa) is the day, while the bright fortnight(śukla pakṣa) is the night for the manes—

tatra kṛṣṇaḥ pakṣo'haḥ śuklo rātriḥ varṣeṇa pauruṣeṇeti śeṣaḥ |

(b) Daiva day (I. 3. 21; p. 36):

Similarly Amarakośa defines a human year is a day for gods which Kṣīrasvāmin elaborates that the northern solstice (uttatrāyaṇa) is the day of the gods while the southern solstice (dakṣiṇāyana) is their night–

tatrottarāyaṇamahaḥ dakṣiṇāyanaṃ rātriḥ |

(c) Brāhma day (I. 3. 21; p. 36):

Amarakośa defines a day of Brahma as 2000 divine yugas and that is equivalent to two kalpas of humans. Seventy one divine yugas is one manvantara. Elaborating on the above Kṣīrasvāmin explains a yuga of gods as 12,000 human years constituting one human caturyuga. Kṣīrasvāmin further adds that 1000 such divine yugas make a day of Brahma which is said to be the time of existence of all beings and the same viz., 1000 divine yugas make a night for Brahma which is believed to be the period of annihilation of all living beings.

Justifying his explanations Kṣīrasvāmin quotes from the text of Manu (I. 69-72):

devairhi ṣaṣṭhyadhikaiḥ tribhirahorātraśatairdivyaṃ varṣaṃ tairdvādaśabhiḥ sahasrairlaukikaṃ caturyugaṃ tacca devānāmekaṃ yugaṃ tatsahasraṃ brahmaṇo dinaṃ bhūtānāṃ sthitikālaḥ tāvatyeva rātrirbhūtānāṃ pralayakālaḥ |

yanmanuḥ—

“catvāryāhuḥ sahasrāṇi varṣāṇāṃ tu kṛtaṃ yugam | tasya tāvatī saṃdhyā saṃdhyāṃśaśca tathāvidhaḥ | itareṣu sasaṃdhyeṣu sasaṃdhyāśeṣu ca triṣu | ekāpāyena vartante sahasrāṇi śatāni ca | yadetatparisaṃkhyātamādāveva caturyugam | etad dvādaśasāhasraṃ devānāṃ yugamucyate | daivikānāṃ yugānāṃ tu sahasram parisaṃkhyayā | brāhmamekamaharjñeyaṃ tāvatī rātrirucyate |” III. 10. (iii) Saṃvartaḥ (I. 3. 22; p. 36)–

Dissolution: Amarakośa mentions samvarta, pralaya, kalpa, kṣaya and kalpānta as synonyms for dissolution. Kṣīrasvāmin while explaining the final dissolution of the world also adds three more words to denote the same as–saṃhāraḥ, yugātyayaḥ and parivartaḥ. It is to be noted here that by the word saṃhāraḥ he refers to destruction of the present world; yugātyaya means the expanding of the existing last yuga; the third word is important in that it refers to the transformation i.e., it indicates the re-vitalizing of the earth.