A more thorough explanation:

Definition: A summoner is a historical petty officer who was responsible for summoning parties to appear in court. They were also known as nuntius(3). The summoner's primary duty was to give notice to the defendant to obey the original writ. This notice was given by summons, which was a warning to appear in court. The summoner was usually accompanied by two of the sheriff's messengers.

Example: In medieval England, summoners were appointed by the church courts to summon people to appear before the ecclesiastical courts. They were responsible for ensuring that people attended church and paid their tithes.

Explanation: The example illustrates how summoners were responsible for ensuring that people attended church and paid their tithes. They would summon people to appear before the ecclesiastical courts if they failed to comply with these requirements.