The works of Ādi Śaṅkarācārya

Sanatsujātīyam

p. 278

p. 278

ब्रह्मचर्यव्रतस्यास्य प्रथमः पाद उच्यते ॥ ९ ॥

In plain words

This is called the first quarter of the vow of brahmacarya.

Close to the Sanskrit

Of this vow of brahmacarya, the first quarter is said.