द्वितीयं प्राप्यानुपूर्व्याज्जन्मोपनयनं द्विजः ।
वसन्गुरुकुले दान्तो ब्रह्माधीयीत चाहुतः ॥
dvitīyaṁ prāpyānupūrvyāj janmopanayanaṁ dvijaḥ |
vasan guru-kule dānto brahmādhīyīta cāhutaḥ ||
(Śrīmad Bhāgavatam: 11.17.22)
“After receiving in sequence the second birth, the upanayana [-saṁskāra], and being invited [by a guru], a twice-born (dvija) should dwell in the house of the guru, be disciplined, and study the Veda.”
Commentary
dvijas traivarṇikaḥ, ānupūrvyā iti garbhādhānādi-saṁskāra-krameṇa prathamaṁ śaukraṁ dvitīyaṁ sāvitram upanayanam upanayanākhyaṁ prāpya brahma vedam adhīyīta |
(Excerpt from the Sārārtha-darśinī-ṭīkā)
“After receiving the first [birth], the seminal (śaukra) [birth], the second [birth], the sāvitra, that is, the upanayana [-saṁskāra], meaning, that [birth] known as the upanayana, in sequence, that is, in accord with the [proper] order of saṁskāras beginning from the garbhādhāna, a twice-born (dvija), that is, a member of the three upper varṇas (traivarṇikaḥ) [viz., the brāhmaṇa, kṣatriya, and vaiśya varṇas] should study the Veda (Brahman).”