One verse

Srimad Bhagavatam 12.6.44

12.6.44

तेनासौ चतुरो वेदांश्चतुर्भिर्वदनैर्विभु: । सव्याहृतिकान् सोंकारांश्चातुर्होत्रविवक्षया ॥ ४४ ॥

tenāsau caturo vedāṁś caturbhir vadanair vibhuḥ sa-vyāhṛtikān soṁkārāṁś cātur-hotra-vivakṣayā

tena
with that body of sounds
asau
he
caturaḥ
the four
vedān
Vedas
caturbhiḥ
from his four
vadanaiḥ
faces
vibhuḥ
the all-powerful
sa-vyāhṛtikān
along with the vyāhṛtis (the invocations of the names of the seven planetary systems: bhūḥ, bhuvaḥ, svaḥ, mahaḥ, janaḥ, tapaḥ and satya)
sa-oṁkārān
along with the seed, om
cātuḥ-hotra
the four aspects of ritual sacrifice performed by the priests of each of the four Vedas
vivakṣayā
with the desire of describing

All-powerful Brahmā made use of this collection of sounds to produce from his four faces the four Vedas, which appeared together with the sacred oṁkāra and the seven vyāhṛti invocations. His intention was to propagate the process of Vedic sacrifice according to the different functions performed by the priests of each of the four Vedas.