Garudapurana 1.8.6

1.8.6

antarā sa dvijaśreṣṭhaḥ pādonaṃ bhrāmayeddhara ! /
anena nābhisūtrasya karṇikāṃ bhrāmayecchiva ! //

In between, that best of the twice-born should swing [it] reduced by a quarter, O Hara! / With this thread from the navel, one should trace the pericarp, O Śiva!