Short answer. A search warrant is a written order issued in the name of the People of the Philippines, signed by a judge, and directed to a peace officer. It commands that officer to search for the personal property described in the warrant and to bring that property before the court, per Rule 126, Section 1.
What the law says
A search warrant is an order in writing issued in the name of the People of the Philippines, signed by a judge and directed to a peace officer, commanding him to search for personal property described therein and bring it before the court.
Rule 126, Section 1 — Search warrant defined. Read the full provision →
Whose authority it carries
Like a criminal complaint or information, a search warrant is issued in the name of the People of the Philippines — it is an exercise of state authority, not a private order. Section 1's definition places that authority squarely with a judge, who alone signs the warrant into existence. No other officer, including a prosecutor or law enforcement official, has the authority under this definition to issue a valid search warrant on their own.
Who it commands, and to do what
The warrant is directed to a peace officer, commanding that officer to search for personal property described in the warrant itself and to bring that property before the court. The command is specific to the property described — the definition ties the search to particular items, not an open-ended authorization. Because the command runs to a peace officer specifically, execution of the warrant is meant to be carried out by law enforcement, not by private individuals or other parties.
Why the writing requirement matters
Because a search warrant must be an order in writing, the scope of what the officer is authorized to search for and seize is fixed on paper at the moment the judge signs it. That written record is what later lets a court, or the person searched, verify whether the search stayed within what the warrant actually authorized, rather than relying on the officer's own recollection of an oral instruction.
Why judicial signature alone is required
Placing the power to sign a search warrant exclusively with a judge reflects the same concern that runs through the rest of Rule 126: a search intrudes on a person's privacy and property, so the decision to authorize one is kept with a neutral judicial officer rather than with the police or prosecution seeking the search. A warrant application still has to satisfy the judge that probable cause exists before signature, so the requirement is a substantive check, not merely a formality of whose name appears on the document.