Chānd-Mül, 1879-842. That Gayatri is also the earth, for everything that here exists rests on the earth, and does not go beyond.
Chānd-Śaṃ, 8th c. A.D.yata evamatiśayaphalaiṣā brahmavidyātaḥ sā prakārāntareṇāpi vaktavyeti gāyatrī vā ityādyārabhyate | gāyatrīdvāreṇa cocyate | brahmaṇaḥ sarvaviśeṣarahitasya neti netītyādiśiṣapratiṣedhagamyasya durbodhatvāt | satsvanekeṣu cchandaḥsu gāyatryā eva brahmajñānadvāratayopādānaṃ prādhānyāt | somāharaṇāt itaracchandokṣarāharaṇenetaracchandovyāptyā ca sarvasavanavyāpakatvācca yajñe prādhānyaṃ gāyatryāḥ | gāyatrīsāratvācca brāhmaṇasya mātaramiva hitvā gurutarāṃ gāyatrīṃ tato ’nyadgurutaraṃ na pratipadyate yathoktaṃ brahmāpīti | tasyāmatyantagauravasya prasiddhatvāt | ato gāyatrīmukhenaiva brahmocyate | gāyatrī vā ityavadhāraṇārtho vaiśabdaḥ | idaṃ sarvaṃ bhūtaṃ prāmijātaṃ yatkiñca sthāvaraṃ jaṅgamaṃ vā tatsarvaṃ gāyatryeva | tasyāśchandomātrāyāḥ sarvabhūtatvamanupapannamiti gāyatrīkāraṇaṃ vācaṃ śabdayatyasau gaurasāvaśva iti ca trāyate ca rakṣatyamuṣmānmā bhaiṣīḥ kiṃ te bhayamutthitamityādinā sarvato bhayānnivartyamāno vācā trātaḥ syāt | yadvāgbhūtaṃ gāyati ca trāyate ca gāyatryeva tadgāyati ca trāyate ca vāco ’nanyatvādgāyatryāḥ | gānāttrāṇācca gāyatryā gāyatrītvam || 1 ||
http://www2.hf.uio.no/common/apps/permlink/permlink.php?app=polyglotta&context=record&uid=cc2c77c8-8e41-11ee-937a-005056a97067