Deuteronomy 18: 15-20
God promises to raise up a new prophet from among the people, one who will speak words and commands of God with authority.  They must listen to him. 

1 Corinthians 7: 32-35
At a time of heightened expectation at the nearness of the coming of the Lord, Paul is anxious that people should remain free of new responsibilities and worries. 

Mark 1: 21-28
The public ministry of Jesus begins with a demonstration of genuine authority and power, in both word and deed.