The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized.
The government can't just take your possessions or search your house without a warrant. This is the entire premise of the Fourth Amendment. the Fourth came in response to infringement on property by the British. With the use of "general warrants" and "writs of assistance," British officers could rummage through any house they wanted to and take what they wanted. Colonists hated that, so they put it in the Constitution to stop it.