He said to them, “I watched Satan fall from heaven like a lightning flash. Look, I have given you the authority to trample on snakes and scorpions and over all the power of the enemy; nothing will ever harm you. However, don’t rejoice that the spirits submit to you, but rejoice that your names are written in heaven.”
In that same hour He rejoiced in the Holy Spirit and said, “I praise You, Father, Lord of heaven and earth, because You have hidden these things from the wise and the learned and have revealed them to infants. Yes, Father, because this was Your good pleasure. All things have been entrusted to Me by My Father. No one knows who the Son is except the Father, and who the Father is except the Son, and anyone to whom the Son desires to reveal Him.” Then turning to His disciples He said privately, “The eyes that see the things you see are blessed! For I tell you that many prophets and kings wanted to see the things you see yet didn’t see them; to hear the things you hear yet didn’t hear them.”
The Seventy returned understandably ecstatic. Even the demons obeyed them under the authority of Jesus' name! Jesus does not reprimand their joy, but he seeks to refocus it. They are to rejoice in their salvation, not in their derived power over the demons. They had witnessed the disciples inability to cast demons out of a boy, but they had successfully commanded the forces of darkness.
Various interpretations are given of the statement, "I saw Satan fall like lightening." This either refers to Satan's original fall after leading the insurrection against God, or it signifies his loss of power as the kingdom of God came near and his fallen angels were ordered around by a band of regular Jewish men. I grew up in the mountains hearing tales of "snake handling" churches. If your faith is strong, those venomous snakes won't bite, or at least the bites won't hurt. Although Paul survives a snake bite while marooned at Malta, I think this passage is a figurative one. Snakes and serpents likely refers to Satan, the demons, and/or those who would stand in the way of the gospel.
Why does Jesus tell his disciples to not take joy in their own successes, even spiritual ones? The joy of the Lord is our strength (Nehemiah 8:10), and he is our only true source of joy. In good times and bad, in success or loss, we are assured of victory in Jesus. He has power over any worldly or supernatural force conspiring against us. Jesus came into the world to overthrow the evil one (John 12:31). Although it is unlikely we will cast out any demons, as disciples of Jesus we have been given spiritual authority and power for overcoming the works of darkness and evil (1 John 2:13-14).
Jesus' prayer contains a warning that pride can keep us from the love and knowledge of God. Those considered wise were blinded by their own beliefs and self-righteousness from seeing the kingdom of God which was before their very eyes. Humility, not feelings of inferiority but the realization that our worth comes from Christ, leads us to a true recognition of who we are in God and of our dependence on him. Those with the simple faith of a child receive the kingdom of God. God opposes the proud, but gives grace to the humble (Prov. 3:34, James 4:6). Jesus is the revelation of the one true God.
Praise the God and Father of our Lord Jesus Christ. According to His great mercy, He has given us a new birth into a living hope through the resurrection of Jesus Christ from the dead and into an inheritance that is imperishable, uncorrupted, and unfading, kept in heaven for you. You are being protected by God’s power through faith for a salvation that is ready to be revealed in the last time. You rejoice in this, though now for a short time you have had to struggle in various trials so that the genuineness of your faith—more valuable than gold, which perishes though refined by fire—may result in praise, glory, and honor at the revelation of Jesus Christ. You love Him, though you have not seen Him. And though not seeing Him now, you believe in Him and rejoice with inexpressible and glorious joy, because you are receiving the goal of you faith, the salvation of your souls. Concerning this salvation, the prophets who prophesied about the grace that would come to you searched and carefully investigated. They inquired into what time or what circumstances the Spirit of Christ within them was indicating when He testified in advance to the messianic sufferings and the glories that would follow. It was revealed to them that they were not serving themselves but you. These things have now been announced to you through those who preached the gospel to you by the Holy Spirit sent from heaven. Angels desire to look into these things. 1 Peter 1:3-12