The characteristics of hardness of heart are in this passage. Those elders and family chiefs did this to their own people. They did it despite their calling and their privileges: the deliverances of the Lord out of Babylon, the provision of a way back to Judah and Jerusalem, the repossessing their lands, and the sympathy of the Persian overlords. Everything was provided for them and yet they could still act completely without feeling and compassion. We read in chapter 2 how some of the nobles and the elders ‘put not their hands to the work.’ That is the effect it can have. That is how callous we can be. In the same way husbands, wives, can have cold wars, and be antagonistic to each other all day. They can fail to show patience and long-suffering and love and care all the time. Hardness of heart is terrible once it gets hold of us. We can ignore brothers and sisters in the Lord, and have zero sensitivity or compassion or understanding. In churches, you have some people: they are saved, they love the Lord, their lives have been turned round; God has blessed them abundantly, but you never see them volunteer for anything. We can have areas of our lives that we just don't feel about. There are churches that won't start Sunday Schools, and the neighbourhoods are teeming with children. They don’t seem to have any heart for it. They come into the church, worship the Lord, have fellowship with one another, but have no heart for the world around. It can happen to us all.
Christians are capable of explaining away God's law. We hear of pastors in American who are wealthy men accepting huge salaries, owning multiple properties. They are not even Prosperity Gospel people; there are some Reformed people too. The Scriptures is against that, but everything is explained away. These rulers and princes of the people would have found a way of explaining away why they were taking interest from the people, at exorbitant rates, over long periods of time and impoverishing them, even though the law of Moses forbade it. They would have had an explanation; you can be sure.