Let a Brahmana who desires to perform austerities, constantly repeat the Veda; for the study of the Veda is declared (to be) in this world the highest austerity for a Brahmana.
आ हैव स नखाग्रेभ्यः परमं तप्यते तपः । यः स्रग्व्यपि द्विजोऽधीते स्वाध्यायं शक्तितोऽन्वहम् ॥ १६७ ॥
Verily, that twice-born man performs the highest austerity up to the extremities of his nails, who, though wearing a garland, daily recites the Veda in private to the utmost of his ability.
A twice-born man who, not having studied the Veda, applies himself to other (and worldly study), soon falls, even while living, to the condition of a Sudra and his descendants (after him).
According to the injunction of the revealed texts the first birth of an Aryan is from (his natural) mother, the second (happens) on the tying of the girdle of Munga grass, and the third on the initiation to (the performance of) a (Srauta) sacrifice.
तत्र यद् ब्रह्मजन्मास्य मौञ्जीबन्धनचिह्नितम् । तत्रास्य माता सावित्री पिता त्वाचार्य उच्यते ॥ १७० ॥
Among those (three) the birth which is symbolised by the investiture with the girdle of Munga grass, is his birth for the sake of the Veda; they declare that in that (birth) the Sivitri (verse) is his mother and the teacher his father.