Albert Barnes on Matthew 25:27

The exchangers. The exchangers were persons who were in the habit of borrowing money, Or receiving it on deposit at a low rate of interest, to be loaned to others at higher interest. They commonly sat by tables in the temple, with money ready to exchange or loan. See Mt 21:12. This money was left with the servant, not to exchange, nor to increase it by any such idle means, but by honest industry and merchandise; but since he was too indolent for that, he ought at least to have loaned it to the exchangers, that his master might have received some benefit from it.

With usury. With interest, increase, or gain. The word usury, in our language, has a bad signification, meaning unlawful or exorbitant interest. This was contrary to the law, Ex 22:25, Lev 25:36. The original means gain, increase, or lawful interest.