गोविन्द भाष्य (श्रील बलदेव विद्याभूषण - अचिन्त्यभेदाभेद वेदान्त ब्रह्मसूत्र भाष्य सटीक)

svādhyāyo 'dhyetavyaḥ
"One should study the Vedas."
In this way one is ordered to study all the Vedas. In the Smṛti-śāstra it is said:
vedaḥ kṛtsno 'dhigantavyaḥ sa-rahasyo dvijanmanā
"A brāhmaṇa should study the entire Veda, including even its confidential
portions."
The word "samācāre" in this sūtra means "because all are qualified to perform
all pious rituals". The Smṛti-śāstra confirms this in the following words:
sarva-vedokta-mārgeṇa
karma kurvīta nityaśaḥ
ānando hi phalaṁ yasmāc
chākhā-bhedo hy aśakti-jaḥ
sarva-karma-kṛtau yasmād
aśaktāḥ sarva-jantavaḥ
śākhā-bhedaṁ karma-bhedaṁ
vyāsas tasmād aciklpad
"Following the path of all the Vedas, one should regularly perform pious
rituals. Bliss is the result attained by this. The Veda was divided into different
branches because the people were not able to perform all the pious deeds described
in the Veda. That is why Vyāsa divided the Veda into many branches and the one
collection of pious rituals into many collections."
Therefore, if a person is able to do so, he may understand the Supreme by
performing all the spiritual practices described in all the branches of the Vedas. In
the next sūtra the author gives an example of indirect reasoning leading to the
same conclusion.
Sūtra 4
sava-vac ca tan niyamaḥ
sava—yajñas; vat—like; ca—and; tat—that; niyamaḥ—rule.