When the Lord rebuked Pharisees and scribes in Mt 23, he said among others the following.

(Mt 23:34) Wherefore, behold, I send unto you prophets, and wise men, and scribes: and some of them ye shall kill and crucify; and some of them shall ye scourge in your synagogues, and persecute them from city to city

In the verse above the Lord mentioned that he would send scribes. The scribes whom the Lord sends are believers. They love God. Ezra is one Old Testament example of a scribe sent by the Lord.

(Ezr 7:6) This Ezra went up from Babylon; and he was a ready scribe in the law of Moses, which the LORD God of Israel had given: and the king granted him all his request, according to the hand of the LORD his God upon him.
(Ezr 7:7) And there went up some of the children of Israel, and of the priests, and the Levites, and the singers, and the porters, and the Nethinims, unto Jerusalem, in the seventh year of Artaxerxes the king.
(Ezr 7:8) And he came to Jerusalem in the fifth month, which was in the seventh year of the king.
(Ezr 7:9) For upon the first day of the first month began he to go up from Babylon, and on the first day of the fifth month came he to Jerusalem, according to the good hand of his God upon him.
(Ezr 7:10) For Ezra had prepared his heart to seek the law of the LORD, and to do it, and to teach in Israel statutes and judgments.

Ezra was a scribe and he was faithful to the Lord. He was committed not only to teach the law but also to do it (Ezr 7:10). The hand of the Lord was on him (Ezr 7:6). Ezra was also a priest, a descendant of Eleazar (Ezr 7:1-5). The fact that he had faith can be seen in this passage.

(Ezr 8:21) ... I proclaimed a fast there, at the river of Ahava, that we might afflict ourselves before our God, to seek of him a right way for us, and for our little ones, and for all our substance.
(Ezr 8:22) For I was ashamed to require of the king a band of soldiers and horsemen to help us against the enemy in the way: because we had spoken unto the king, saying, The hand of our God is upon all them for good that seek him; but his power and his wrath is against all them that forsake him.
(Ezr 8:23) So we fasted and besought our God for this: and he was intreated of us.

After Ezra came to Jerusalem, he was told about a sin of the people.

(Ezr 9:1) Now when these things were done, the princes came to me, saying, The people of Israel, and the priests, and the Levites, have not separated themselves from the people of the lands, doing according to their abominations, even of the Canaanites, the Hittites, the Perizzites, the Jebusites, the Ammonites, the Moabites, the Egyptians, and the Amorites.
(Ezr 9:2) For they have taken of their daughters for themselves, and for their sons: so that the holy seed have mingled themselves with the people of those lands: yea, the hand of the princes and rulers hath been chief in this trespass.

The problem was not that they were married to persons of different nationality but that they were married to persons of different religion (Ne 13:26). Instead of uniting themselves with people practicing abominations (Ezr 9:1), the Israelites were to separate themselves and be holy to the Lord (De 14:2). Now, Ezra was also a good priest. He earnestly prayed and fasted when he found out about this sin.

(Ezr 9:3) And when I heard this thing, I rent my garment and my mantle, and plucked off the hair of my head and of my beard, and sat down astonied.
(Ezr 9:4) Then were assembled unto me every one that trembled at the words of the God of Israel, because of the transgression of those that had been carried away; and I sat astonied until the evening sacrifice.
(Ezr 9:5) And at the evening sacrifice I arose up from my heaviness; and having rent my garment and my mantle, I fell upon my knees, and spread out my hands unto the LORD my God

(Ezr 10:1) Now when Ezra had prayed, and when he had confessed, weeping and casting himself down before the house of God, there assembled unto him out of Israel a very great congregation of men and women and children: for the people wept very sore.

Ezra continued to mourn even after the people committed themselves to act concerning this sin.

(Ezr 10:6) Then Ezra rose up from before the house of God, and went into the chamber of Johanan the son of Eliashib: and when he came thither, he did eat no bread, nor drink water: for he mourned because of the transgression of them that had been carried away.

Then Ezra and certain leaders of the people addressed this issue for a few months (Ezr 10:16-17).

After the walls of Jerusalem were built, the people gathered in the first day of the seventh month to hear the law (Ne 8:2). In this context Ezra is again mentioned.

(Ne 8:1) And all the people gathered themselves together as one man into the street that was before the water gate; and they spake unto Ezra the scribe to bring the book of the law of Moses, which the LORD had commanded to Israel.
(Ne 8:2) And Ezra the priest brought the law before the congregation both of men and women, and all that could hear with understanding, upon the first day of the seventh month.
(Ne 8:3) And he read therein before the street that was before the water gate from the morning until midday, before the men and the women, and those that could understand; and the ears of all the people were attentive unto the book of the law.

"Ezra had prepared his heart to seek the law of the LORD, and to do it, and to teach in Israel statutes and judgments" (Ezr 7:10). The passage above mentions one occasion in which he taught the people.

(Ps 37:30) The mouth of the righteous speaketh wisdom, and his tongue talketh of judgment.