p. 279
आचार्येणात्मकृतम् आत्मनः कृतम् उपकारं विजानन् ज्ञात्वा अर्थं वेदार्थं परमपुरुषार्थं ज्ञात्वा च अवगम्य भावितोऽस्मीत्यनेन भावितोऽस्मीति स्वाभाविकचित्सदानन्दाद्वितीयब्रह्मात्मना यथावदुत्पादितोऽस्मीति चिन्तयन् तमाचार्यं प्रति हृष्टबुद्धिः सन् यत् आत्मनः कृतार्थत्वं मन्यते, स वै तृतीयो ब्रह्मचर्यस्य पादः ॥
In plain words
Recognizing the spiritual benefit rendered by the teacher, having grasped the ultimate import of the scriptures and the supreme goal of human life, and realizing deeply 'I am awakened'—reflecting that one has been truly brought forth as the very nature of non-dual Brahman, which is pure consciousness, existence, and bliss—the student turns toward the teacher with a joyful heart, knowing himself to be completely fulfilled. This indeed is the third quarter of spiritual studentship.
Close to the Sanskrit
Recognizing the benefit done to the self by the teacher, knowing the meaning, knowing the Veda's meaning and the supreme human goal, and having comprehended 'I am brought into being' through this—thinking 'I have been properly brought into being as the natural non-dual Brahman-Self of consciousness, existence, and bliss'—reflecting thus toward that teacher with a joyous mind, whatever he considers to be the fulfillment of his own self, that indeed is the third quarter of brahmacarya.