Deuteronomy 13:1-18
A false prophet is particularly dangerous when he rises up from amongst the people of God. All the apostles sound the alarm against these spreaders of perverse doctrines who "by good words and fair speeches deceive the hearts of the simple" (Romans 16:18; 2 Peter 2:18; 1 John 2:19; Judges 1:4). "Thou shalt not hearken . . ." commands v. 3 – and on the contrary: "Ye shall walk after the LORD your God . . . and obey his voice" (v. 4). Safety for the Good Shepherd’s sheep consists in knowing His voice well (John 10:4-5). They then have no trouble in distinguishing – in order to run away from – the voice of a stranger. A second danger which is no less subtle is that we pass on bad influences, all the more to be feared when they come from an intimate friend. "Be not deceived: evil communications corrupt good manners" (1 Corinthians 15:33). Let us have the courage to break off a relationship which is tending to lead us away from the Lord (Luke 14:26). Finally, evil could take on a collective nature: an entire city could be infected by it. The faithful believer is called to withdraw from all religious circles in which, in the light of the Word of God, he will be tainted by iniquity (2 Timothy 2:19).