Jamieson, Fausset and Brown on Matthew 25:24

24. Then he which had received the one talent came and said, Lord, I knew thee that thou art an hard man--harsh. The word in Luke (Lu 19:21) is "austere."

reaping where thou hast not sown, and gathering where thou hast not strawed--The sense is obvious: "I knew thou wast one whom it was impossible to serve, one whom nothing would please: exacting what was impracticable, and dissatisfied with what was attainable." Thus do men secretly think of God as a hard Master, and virtually throw on Him the blame of their fruitlessness.