Verse 7.11.1

तेजो वावाद्भ्यो भूयस्तद्वा एतद्वायुमागृह्याकाशमभितपति तदाहुर्निशोचति नितपति वर्षिष्यति वा इति तेज एव तत्पूर्वं दर्शयित्वाथापः सृजते तदेतदूर्ध्वाभिश्च तिरश्चीभिश्च विद्युद्भिराह्रादाश्चरन्ति तस्मादाहुर्विद्योतते स्तनयति वर्षिष्यति वा इति तेज एव तत्पूर्वं दर्शयित्वाथापः सृजते तेज उपास्स्वेति ॥ ७.११.१ ॥

tejo vāvādbhyo bhūyastadvā etadvāyumāgṛhyākāśamabhitapati tadāhurniśocati nitapati varṣiṣyati vā iti teja eva tatpūrvaṃ darśayitvāthāpaḥ sṛjate tadetadūrdhvābhiśca tiraścībhiśca vidyudbhirāhrādāścaranti tasmādāhurvidyotate stanayati varṣiṣyati vā iti teja eva tatpūrvaṃ darśayitvāthāpaḥ sṛjate teja upāssveti || 7.11.1 ||

1. Fire [or, heat] is certainly better than water. That fire, taking air as its support, heats the sky. Then people say: ‘It is very hot. The body is burning. It will rain soon.’ Fire first produces these signs, and then creates the rain. This is why there is lightning going straight up or going sideways in a zigzag manner, and along with it thunder. This is why people say: ‘There is lightning and thunder. It will rain soon’.

Word-for-word explanation:

Tejaḥ vāva adbhyaḥ bhūyaḥ, fire is certainly superior to water; tat vai etat, that [fire]; vāyum āgṛhya, taking the support of air; ākāśam abhitapati, heats the sky; tadā, then; āhaḥ, people say; niśocati, it is very hot; nitapati, it is burning; varṣiṣyati vai iti, there will be rain; tejaḥ eva tat, there is fire; pūrvam, first; darśayitvā, showing; atha apaḥ, then water; sṛjate, creates; tat etat, that [fire]; ūrdhvābhiḥ ca tiraścībhiḥ ca, going upwards and sideways in an irregular way; vidyudbhiḥ, with lightning; āhrādāḥ, the roar of thunder; caranti, moves about; tasmāt, this is why; āhuḥ, people say; vidyotate, there is lightning; stanayati, there is thunder; varṣiṣyati vai iti, there will certainly be rain; tejaḥ eva tat pūrvam darśayitvā, first heat is seen; atha apaḥ sṛjate, then it creates water; tejaḥ upāssva iti, worship fire.

Commentary:

In Indian philosophy, there is no such thing as creation—that is, something created out of nothing. But there is manifestation. This universe is always there, only sometimes it is manifest and sometimes it is not. When it is not manifest it is in a seed form. But Brahman is the essence of everything. It is infinite Existence, and that Existence is Consciousness.

The first manifestation of Brahman is space. After that comes air and then fire. Water comes from fire, or energy. Finally, earth comes from water. Some things in this universe are gross, and some are subtle, but according to Indian philosophy all are by-products of earth, water, fire, air, and space. This universe is nothing but a permutation and combination of these five elements.

Tejas means fire, heat, or energy. Fire is superior to water in the sense that it is the cause, and the cause is always superior to the effect. Fire is said to take air as its support and then make the air motionless through its power. The heat then spreads through space. We all know that when the atmosphere becomes very hot, it will soon rain. Also, before it rains we often see lightning and hear the roar of thunder. This indicates that the atmosphere is surcharged with electricity. So it is said that fire is the cause of water. Fire manifests itself as water.

It is not that these elements are separate things.