Luke Chapter 10 takes place near the end of Jesus’ earthly ministry. As he prepares to leave for Jerusalem and his final journey to the cross, Jesus has one last preaching tour planned. He sends out seventy of his disciples in pairs to prepare the towns and villages for his arrival. Jesus sends them out with his blessing and instructs them to heal the sick and give them the authority to cast out demons. When the disciples return, they return with joy and state that even devils submit to them in Jesus's name.
Jesus rejoices with his disciples over their wonderful work in his name, but he also challenges them regarding their misplaced joy. Does their happiness stem from what they accomplished, or is there something bigger at play? A few verses later, in Luke 10:20, Jesus tells them that while the task he has given them is important, they must not lose sight of the greater picture. There was a better reason for them to rejoice - their names are written in heaven. When temporary authority is no longer present, celebrating it will only result in loss of happiness. Our delight should primarily be ignited by eternal truths - God has written our names in heaven with the blood of his Son. God's kingdom is where we will find our true joy and confidence.

Dear Heavenly Father, I am so glad that You have left the Holy Spirit as a helper for me. I pray for its indwelling power, which enables me to cast out evil spirits in Your name. Help me to be a disciple of Yours and bring comfort to those in need of Your healing. I am overjoyed that You have welcomed me into Your kingdom and that I will be with You forever. Lord, thank You for providing me with this eternal joy. 
In Jesus's name I pray, Amen.