There were many times when Jesus, while casting demons out of people, commanded them to be silent (Luke 4:33 - 35, 41, Mark 3:11 - 12). Why did he do this? He did this so that the demons would not publically reveal his true identity (Mark 1:34, Luke 4:41).
One noteworthy example of silencing demons came when Jesus was teaching in a synagogue. As he taught, an unclean spirit began to shout that he was God's son. Christ quickly commanded the disobedient spirit to "hold thy peace" (Mark 1:25, KJV). Taken literally, the Greek word for this phrase means that Jesus told the demon to close its mouth with a muzzle (see 1Corithians 9:9)!
The more the merrier?
The most common form of possession by demons is one evil spirit entering into a human (e.g. Satan possessing Judas). That said, Scripture indicates there may be no limit to the number of fallen angels that can torment someone.
Mary Magdalene, at one time, was plagued with seven devils (Luke 8:2). Jesus spoke of an unclean spirit finding seven of his "friends" so that they all could increase a person's suffering (Matthew 12:43 - 45).
Christ, in one of his most spectacular miracles, cast out several thousand demonic spirits from a Gadarenes' man (Luke 8:26 - 30). The spirits were allowed to possess a herd of 2,000 pigs (Mark 5:13), showing that more than one demon can also enter into and torment an animal.
Freed from torture
Although the Bible mentions Christ casting out demons from countless people (Mark 1:34, Luke 4:41), it records only a few details from seven of them (Mark 1:23 - 26, 5:1 - 13, 9:17 - 27, Matthew 9:32 - 33, 15:22 - 28, Luke 8:2, 11:14).
Jewish Rabbinic tradition taught that legions of demons lie in wait to harm a person if they used an even number of objects. For example, care had to be taken not to use an even number of cups. The rare exception to this rule was on Passover night, when it was believed an even number of cups could be used without risking harm. This superstitious notion regarding the power of evil led to the widely held belief that odd numbers are lucky.
Lost in translation
The word "demon" is not found in the King James Bible. It does appear, however, in a few Bible translations such as the New International Version and others. Additionally, the word "demoniac," a modern term commonly used to denote a possessed person is also not used in the KJV.
Did you know that at least one of the demons did God a favor? The Eternal, greatly displeased with King Ahab, wanted him to die in battle. An evil spirit offered to induce the king to fight by being a lying spirit in the mouth of his prophets. His suggestion was not only accepted but also proved to be successful (1Kings 22:19 - 23, 37 - 40)!
Miscellaneous Demon Trivia
At least thirty-six Bible books mention evil spirits (including Satan) or their activities.
King David is the only person listed in Scripture who had the God-given ability to use music to chase away demons (1Samuel 16:14 - 23).