Final answer:
The phrase pertains to a sentry's duty in the military to obey and pass on orders from superiors, which is part of maintaining military discipline and chain of command.
Step-by-step explanation:
The phrase 'To receive, obey and pass on to the sentry who relieves me all the orders from the commanding officer, officer of the day, and officers and noncommissioned officers of the guard only' refers to the responsibilities and procedures expected from a military sentry regarding the communication of orders. This phrase describes one of many general orders that sentries are expected to follow to maintain discipline and proper functioning within the military hierarchy. These orders are essential to ensure that the chain of command is respected, and that each sentry understands their duty to accurately relay commands. The number attached to this general order can vary by country and military branch, but it is often memorized by military personnel during their training.
Military orders and the expectation of absolute obedience are a part of military regulations and command hierarchy. This is both a method of maintaining order and a strategy to instill a sense of duty and responsiveness in soldiers, reflecting the importance of structure within military institutions.