Matthew 12:34

Ye offspring of vipers (gennhmata ecidnwn). These same terrible words the Baptist had used to the Pharisees and Sadducees who came to his baptism ( Matthew 3:7 ). But these Pharisees had deliberately made their choice and had taken Satan's side. The charge against Jesus of being in league with Satan reveals the evil heart within. The heart "spurts out" (ekballei) good or evil according to the supply (treasure, qhsaurou) within. Verse Matthew 33 is like Matthew 7:17-19 . Jesus often repeated his crisp pungent sayings as every teacher does.