The promise of a future redemption brings up a highly practical question. After suffering the long exile, the population of the Israelites has dwindled to a mere fraction of what it once was. How can the ruined cities of the land of Israel possibly be settled again by such a small group? The answer lies in a divine promise for a miracle of unprecedented demographic growth [מלבי״ם, אברבנאל]. The primary approach among commentators is that God will wait for the Israelites to turn to Him and explicitly pray for this specific blessing [רש״י, מצודת דוד]. Once they make this request, God will gladly answer their prayers and grant them a massive increase in numbers [רד״ק, ביאור שטיינזלץ].
At the heart of this promise is a vivid comparison between the people and a flock of sheep. On a basic level, this means the Israelites will multiply to enormous proportions, just as a flock of sheep grows rapidly and abundantly [רש״י, מצודת דוד, רד״ק]. However, this growth will be a miraculous blend of the natural and the human. While the people will multiply with the incredible speed characteristic of animals, they will perfectly maintain their human dignity, intellect, and distinct identity [מלבי״ם, אברבנאל, ביאור שטיינזלץ].
Beyond simple physical numbers, comparing the people to a flock carries deep spiritual meaning. This massive population boom will not lead to an increase in sin or wickedness. Instead, it will be defined by an extraordinary level of holiness. Just as massive flocks of holy sheep once filled Jerusalem during the pilgrimage festivals to be offered as joyful sacrifices before God, the Israelites will fill their rebuilt cities with profound holiness, joy, and spiritual delight [מלבי״ם, אברבנאל, צאינה וראינה]. Additionally, this imagery recalls the flock of Jethro that Moses once tended. That specific flock enjoyed miraculous care and was never harmed by wild beasts, which serves as a powerful hint to the divine protection that will completely surround the people [אברבנאל].
A unique approach views the blending of sheep and human imagery as a reflection of God's complex and compassionate relationship with His people. When the Israelites sin, God treats them with gentle forgiveness, viewing them like a mindless sheep that accidentally breaks a tree in a garden, a mistake for which an owner would not deal out a harsh punishment. On the other hand, when they perform commandments and good deeds, God views them fully as intelligent, reasoning humans, rewarding them completely for actively choosing to do good [צאינה וראינה].