Matthew 25: 14-30 When the master returned, he praised the first two men for they had doubled his money and he put them in charge of even more things. But the third servant, blamed the master for him, not doing anything with the talent, in a way he accused the master of demanding more than was reasonable, out of proportion to what he had given him. He even went so far as to say he was afraid. I would say he was worried about what he perceived as his own inability to do what he was called to do.
When God speaks to you, when He calls you, you can’t respond based on your education, your knowledge, or your own understanding. Your ability to respond in spiritual things, is measured by the promises of God. If you try to answer God’s call with your own ability, before long you will fail and worry will set in and you will find yourself like the servant blaming God. “God you expect more of me than you give me power to do.” “You demand too much of me” “I can not do what you ask of me because of where you, God, have placed me”