God's promise of redemption carries a profound message of hope and certainty, assuring the people that divine salvation operates on an exact, predetermined schedule. Even when liberation seems endlessly delayed, it is moving steadily toward its complete fulfillment.
The primary approach among commentators is that this prophecy focuses on the fall of Babylon and the end of that specific exile. The vision is destined for a fixed, appropriate time [מצודת ציון, ביאור שטיינזלץ], set to materialize exactly at the close of seventy years in exile [רש"י, רד"ק, אבן עזרא]. The prophecy actively speaks and testifies about this much-anticipated end. Like breath leaving the mouth, the vision gives voice to a promise that will not disappoint, pause, or fail, guaranteeing its certain reality [רש"י, מצודת ציון, רד"ק, מלבי"ם, ביאור שטיינזלץ].
However, another perspective suggests the prophecy looks far beyond the relatively brief Babylonian exile and gazes into the distant future. Because the time in Babylon was short, the idea of a long delay does not fully apply. Instead, the promised end points to the conclusion of all exiles and the ultimate, final redemption, after which there will be no more oppression [אברבנאל, מצודת דוד, מלבי"ם]. From this viewpoint, the voice of the prophecy is somewhat hidden and incomplete. The exact details of this final, wondrous end were never explicitly spoken, but only subtly hinted at to the prophets [מלבי"ם].
A natural question arises regarding the nature of this waiting period. How can a vision take a long time to arrive, yet not be late? The answer lies in the difference between a prolonged process and a missed deadline. A process may stretch out over a vast period, perhaps even a thousand years, creating the feeling of a delay. Being late, on the other hand, means missing the established appointment. When the distant, predetermined moment finally arrives, the vision will materialize instantly, without missing its mark by a single second [מלבי"ם]. Therefore, the call to wait is a direct message to the exiled people. Even as the years multiply, they must never abandon hope, trusting that the final end will arrive precisely on God's schedule [רד"ק, מצודת דוד].