Read: Matthew 10:1-4
And he called to him his twelve disciples and gave them authority over unclean spirits, to cast them out, and to heal every disease and every affliction. (Matthew 10:1 ESV)
Authority is generally pretty easy to recognize. We recognize the authority of police by their uniforms, badges, or vehicles. Firemen are recognized by their uniforms and equipment. First responders by their sirens and ambulance.
All of these things are not authority. They are only the tools that allow the ones who wield them to utilize and represent their authority by completing their jobs. Police use those tools to enforce the law, firemen to aid civilians and stop fires, and first responders to rescue people of provide emergency medical assistance. Each of these people are operating under a type of authority given to them by a larger governing power.
Jesus was the disciples' larger governing power. As he was the face of God before the Twelve he represented the interest and authority of God. He passed this authority on to his disciples.
The Apostle Paul later wrote that all Christians were Christ's ambassadors. Each of us carry an official mark of authority that recognizes us as official representatives of the Kingdom of God. In some way, on some level, that bestows upon us an inherent authority. The disciples were granted authority to cast out demons and to heal people. What does that kind of authority mean for you and I?