In Matthew 12, Jesus is accused of performing miracles not by the power of God but by the power of Satan. From then on, Jesus speaks in parables.
The English word parable comes from the word paraballo: para meaning alongside and ballo meaning to throw. Essentially, parables are truths thrown alongside. A parable has a context and a specific meaning within that context – a truth that points to a bigger truth – and those who are receptive will look for the underlying truth.