A prophet's calling is defined not only by the message he carries but by the specific people he is chosen to address. God directs the prophet specifically toward the community of exiles living along the banks of the Chebar River [רד״ק, מצודת דוד]. This exact focus highlights the unique nature of his mission. While other prophets, such as Jeremiah, were appointed to guide the inhabitants of the Land of Israel, this mission is strictly dedicated to the exiled community. Furthermore, the prophet is sent exclusively to his own people. Even when his prophecies concern foreign nations, the intended audience for those messages remains strictly his fellow Israelites [מלבי״ם].
The divine instruction emphasizes the act of communication multiple times, a detail that is explained in several ways. The primary approach among commentators is that this serves as a directive to persist. The prophet must rebuke and speak to the people over and over again, maintaining the hope that they will eventually listen [רד״ק, מצודת דוד, ביאור שטיינזלץ]. Another perspective suggests this outlines a dual method of delivery. The prophet is expected to speak with the people at length, yet he must constantly clarify that these words do not originate from his own mind. With every message, he must declare that he speaks strictly on behalf of God [מלבי״ם]. A third view outlines a two-step process in his duty: first experiencing the prophecy, and then verbally relaying those words to the audience [רד״ק].
Ultimately, the boundaries of the prophet's responsibility are clearly set. He is obligated to deliver God's message under all circumstances, regardless of whether the people choose to listen or ignore him [רש״י, מצודת דוד]. His duty is simply to voice the truth with the hope that it will be received. The actual choice to heed the warning, however, is entirely out of his hands. Because the audience is deeply stubborn, even if they recognize the truth of his words, the final decision to act upon them rests solely with them [ביאור שטיינזלץ].