It comes across rather tamely in our translation – ‘Also I said, It is not good that ye do.’ Nehemiah is outlining the damage that their behaviour has caused.
Christians are to bear one another’s burdens and be on the lookout for those in need. If there is help needed, it would be a shameful thing for the well off to provide help in a way that takes advantage. The rich should not take advantage of the poor, and the poor should not take advantage of the rich. When we lend or give to another, as Christ has taught us, we do it to the Lord himself.