Luke 10:18-20 (NIV)
He replied, “I saw Satan fall like lightning from heaven. I have given you authority to trample on snakes and scorpions and to overcome all the power of the enemy; nothing will harm you. However, do not rejoice that the spirits submit to you, but rejoice that your names are written in heaven.”
The snakes and scorpions may be meant literally in this passage but in the context of Satan falling and the power of the enemy we have to assume that Jesus is primarily talking about all kinds of spiritual opposition. No doubt at least in part the spiritual powers of evil Paul speaks of in Ephesians 6. If we have no reason to fear our only real enemy, Satan then we need have no fear at all. What can people do against us? Jesus is not promising a pain free existence but a life where even when opposition comes we need not be discouraged God himself redeems and transforms.
Father, help us to know real confidence as we take each step with you.