Bhagavatapurana 3.8.16

3.8.16

tasyāṃ sa cāmbho-ruha-karṇikāyām avasthito lokam apaśyamānaḥ /
parikraman vyomni vivṛtta-netraś catvāri lebhe 'nudiśaṃ mukhāni //

16. Seated on the fruit-stalk of that lotus and not seeing the world, Svayambhu looked about on all sides in the sky and so had four faces corresponding to the four cardinal points.