In the first year of Daryavesh the Mede, Daniel seems to think that the seventy years of exile are complete. Only 52 years have transpired since the destruction of Jerusalem. According to an opinion stated in the Gemara, which is the opinion of most commentators, Daniel was mistaken. It is hard to imagine an eighteen year mistake over a seventy year period. Instead, Daniel’s calculation corresponds to seventy years from Nevukhadnetzar’s rise to power. Yirmiyahu predicted that only a heartfelt prayer with a true, profound seeking of God, coupled with the passing of seventy years, would bring the redemption. This was the significance of Daniel’s prayer.

Courtesy of the Virtual Beit Midrash, Yeshivat Har Etzion