As Samuel and Saul reach the edge of the city to part ways, Samuel prepares to deliver a fateful, deeply private message from God. To ensure complete secrecy, Samuel needs Saul's servant out of earshot. Rather than directly ordering the young man to move away, Samuel asks Saul to send him ahead. This reflects a standard of basic etiquette: it is inappropriate to issue commands to another person's servant in front of the master. Instead, the master must give the instruction himself [מלבי״ם, אברבנאל]. The goal is for the servant, who has been following behind them, to walk far enough ahead so that he cannot hear the upcoming conversation [רוב הפרשנים].
The servant, however, does not wait for a formal order. The moment he overhears the beginning of Samuel's request, he takes the initiative and immediately moves forward. Only after the young man has distanced himself does Samuel finish speaking to Saul [מצודת דוד].
Now completely alone, Samuel asks Saul to stand with him for a moment [רש״י, רד״ק]. The specific phrasing of this request is understood in a few different ways. Some explain that Samuel is simply asking Saul to stand with him right then and there [מצודת ציון, ביאור שטיינזלץ]. Others note that Samuel is not asking Saul to remain in that spot for an entire day, as Saul continues his journey shortly after. Rather, the request to pause serves as a strong expression meant to emphasize the gravity of the message and to validate the words that are about to be spoken [רד״ק, אברבנאל].
A more symbolic perspective focuses on the exact time of the morning. Because this meeting occurs at the break of dawn, Samuel asks Saul to wait just a little longer until the sky brightens and the sun fully rises. Only then does he plan to share God's message. Waiting for the morning light acts as a subtle hint and a blessing for the future king: just as the sun emerges in its full, radiant strength, so too will Saul's new kingship succeed and shine brightly [אברבנאל, מלבי״ם].