Shiva Purana

siva.sh/siva-purana/vishweshwara-samhita/18/91

जातः पुत्रो मंत्रपुत्रः पितरं पूजयेद्गुरुम् । निमज्जयति पुत्रं वै संसारे जनकः पिता ९१ ।

sanskrit

The son shall therefore adore his preceptor as father unto him. The real father, the physical begetter, drowns the son in the ocean of worldly existence.

english translation

jAtaH putro maMtraputraH pitaraM pUjayedgurum | nimajjayati putraM vai saMsAre janakaH pitA 91 |

hk transliteration by Sanscript