From Nehemiah 5:8
"As far as possible, we have bought back our fellow Jews who were sold to the Gentiles. Now you are selling your own people, only for them to be sold back to us!"
Later, he states that he wasn't taking the usual payments given to the governor, in spite of quite extensive food requirements:
14 Moreover, from the twentieth year of King Artaxerxes, when I was appointed to be their governor in the land of Judah, until his thirty-second year—twelve years—neither I nor my brothers ate the food allotted to the governor. 15 But the earlier governors—those preceding me—placed a heavy burden on the people and took forty shekels[a] of silver from them in addition to food and wine. Their assistants also lorded it over the people. But out of reverence for God I did not act like that... 17 Furthermore, a hundred and fifty Jews and officials ate at my table, as well as those who came to us from the surrounding nations. 18 Each day one ox, six choice sheep and some poultry(T) were prepared for me, and every ten days an abundant supply of wine of all kinds. In spite of all this, I never demanded the food allotted to the governor, because the demands were heavy on these people.
So, he purchased a large number of people out of slavery and provided large amounts of food on a regular basis for the nobles. How did he afford all of this when he was not taking the usual money given to the governors?