Jesus had just been accused of being demonised.  The Pharisees said that He cast out demons by the power of Satan (Matthew 12:22-28). This saying of Jesus might seem rather strange.  Was He really suggesting that people should violently enter other people's houses and steal their possessions?  Of course not!  Jesus was using an illustration to show that the power of Satan would only be overcome by someone who is much stronger than him.  Jesus was saying that Satan is very strong and wickedly thinks that he owns a large house (the world).  But he is not all-mighty … Jesus is … because He is the Almighty God (John 1:1-3).
 
Jesus came to earth to take away Satan's power and to release people who he had held captive in his 'house' (Hebrews 2:14-15).  The 'possessions' in this verse are really people who have been dominated by the Evil One.  Jesus was saying that only He had the power to deal with Satan so that captives can be set free (Luke 4:18-21).  That was His intention (1 John 3:8), and still is.
 
After His baptism, the Spirit led Jesus into the wilderness to confront Satan (Mark 1:12-13).  Jesus won the power contest ... it was like a landlord giving an illegal tenant a legal notice to move out.  When Jesus rose from the dead, all Satan's hopes were dashed as death, his final threat and weapon, was broken and had no enduring power (2 Timothy 1:10).  The devil now knows that Jesus will soon end his reign of terror.  That is why he is stepping up his evil activity like a disturbed hornet (Revelation 12:12).
 
The power of Satan is real.  Not least through his ability to implant tempting lies into our hearts.  Even if they do not realise it, everybody is trapped by him until they are released by Jesus Christ.  As we believe the gospel, confess our sins and receive Christ into our hearts by faith (Ephesians 3:17), then Satan has no right to hold us captive.  As we cry out to the Lord, He will work in us, to help us resist temptation.  He also wants us to work with Him to spread the good news about Jesus so that many other people can be liberated into a new life under His authority.