In Luke 9, Jesus called His disciples together and gave them power and authority over all demons and to cure disease. Jesus had modeled His ministry to them and then empowered them to go and preach the Kingdom of God, and to heal the sick. They were sent as a unit to learn together what it was like to minister with Jesus’ authority and power. They had their first opportunity to represent Christ to the multitudes. When the apostles returned to Him, they told Him everything that they had done.
In Luke 10, Jesus appointed seventy other disciples and sent them two by two into every city and place where He Himself was about to go. As He prepared to send them, He envisioned for them the harvest and the challenges they would face from many hated Jesus. He gave them strict orders on what to take with them. He instructed them with whom they should stay and how to handle people, both those who received them and those who did not. Jesus instructed them to heal the sick and declare, “The kingdom of God has come near you.” (Luke 10:9b NKJV).
Jesus also said that some cities would not receive them. Jesus told the disciples, “But whatever city you enter, and they do not receive you, go out into its streets and say, ‘The very dust of your city which clings to us we wipe off against you.’” (Luke 10:10 NKJV). He pronounced judgment on the cities of Israel that reject His apostolic company which He was sending to them. This continued for a generation after the resurrection of our Lord.
When the seventy returned with joy to Jesus, they said, “Lord even the demons are subject unto us in Your name.” (Luke 10:17b NKJV). Jesus then instructed them further, and underscored their authority by saying, “Behold, I give you the authority to trample on serpents and scorpions, and over all the power of the enemy, and nothing shall by any means hurt you.” (Luke 10:19 NKJV).