Canto 2 -
Ayodhyā-kāṇḍa
Chapter 111: Rāma Agrees to Accept the Throne After Returning to Ayodhyā
Text 2.111.3

पिता ह्येनं जनयति पुरुषं पुरुषर्षभ।
प्रज्ञां ददाति चाचार्यस्तस्मात्स गुरुरुच्यते।।

pitā hy enaṁ janayati puruṣaṁ puruṣa-rṣabha
prajñāṁ dadāti cācāryas tasmāt sa gurur ucyate

pitā hi = a father; enam = him; janayati = gives birth; puruṣam = to a man; puruṣa-ṛṣabha = O prince; prajñām = knowledge; dadāti = bestows; ca = and; ācāryaḥ = a teacher; tasmāt = so; saḥ guruḥ = a guru; ucyate = is called.

O prince, a father gives birth to a man. A teacher bestows him knowledge and so is called a guru.

Here “a father” means “a father and a mother.”

Because one’s teacher gives knowledge, he is superior to one’s mother and father who only give the body because of the following [authoritative] statement:

sa hi vidyātas taṁ janayati. tac chreṣṭhaṁ janma. śarīram eva mātā-pitarau janayataḥ.

“The teacher gives birth to him through knowledge. This birth is superior. The mother and father only give birth to the body.” (Āpastamba Dharma-sūtra 1.1.1.16-18)