We assume that some people have more authority than others, and their right to command is proportional to their power to coerce.    And in worldly terms that is often the case.  But in God's kingdom things are different (Matthew 20:25-28).  He has chosen that His authority is invested in His Word.  That is why Jesus is described as the 'Word', because He was given the full right to speak on behalf of Father God (Matthew 28:18).  

In this passage, Jesus was telling His followers that when they went to various towns telling the gospel truth, those words had the full authority of the Godhead.  Therefore, receiving the truth from one of the 72 new missioners (Luke 10:1-3) was the same as believing what Jesus said, and accepting the authority of God over their lives. Conversely, those who dismissed the gospel from these disciples were rejecting Jesus and all the purposes of God in salvation.

The disciples needed to understand that their authority was not in their personality, passion or powers of persuasion, or in some hierarchical power structure.  The right to command obedience to the gospel was contained in God's Word, the truth given to them by the Holy Spirit (John 16:12-15), so that they could speak God’s truth (Romans 1:16).  The messenger is therefore of far less significance than the message; and the response is not to the messenger but to Father God Himself!

This teaching continues to help the church to see pastoral and evangelistic ministry in God's perspective.  God’s authority is in the Word.   Church leadership and sharing the gospel should not be an 'ego-trip' for enthusiasts, because it is not about us.  When people respond to the gospel we share, there is no reason for self-congratulation: and when they reject it, we have no right to descend into personal despair.  Understanding this should set us free to simply declare ‘the praises of Him who has called us out of darkness into His wonderful light’, as 1 Peter 2:9 tells us.  Yes, people may hate us for it, but do not take it personally ... they are just expressing their rebellion against God (Luke 21:12-19).  When they turn from their sins to the Saviour, and are converted, just be grateful that the seed of the Word has germinated and is starting to bear fruit (Luke 8:10-15).