17 The seventy-two returned with joy and said, "Lord, even the demons submit to us in your name." 18 He replied, "I saw Satan fall like lightning from heaven. 19 I have given you authority to trample on snakes and scorpions and to overcome all the power of the enemy; nothing will harm you. 20 However, do not rejoice that the spirits submit to you, but rejoice that your names are written in heaven."