Ezra 7:10

For Ezra had prepared his heart to seek the law of the Lord,
&c.] To attain to the knowledge of it, that he might be master of it, and expert in it, and know what was not to be done, and what to be done; he had set his heart upon this, bent his studies this way, and taken a great deal of pains in searching into it, in reading of it, and meditating on it;

and to do it;
he was not only concerned to get the theory of it, but to put it in practice, to exercise himself in it, that it might be habitual to him; and the rather, as his view and intentions were not merely for the sake of himself, but

to teach in Israel statutes and judgments:
and therefore it was not only necessary that he should have a large and competent knowledge of the laws, moral, ceremonial, and civil, but that he should act according to them himself, that so by his example, as well as by his instructions, he might teach the people.