Daniel 9:24

Seventy weeks have been decreed for your people and your holy city, to finish the transgression, to make an end of sin, to make atonement for iniquity, to bring in everlasting righteousness, to seal up vision and prophecy, and to anoint the most holy place.

NASB

Seventy weeks.  This term literally means seventy sevens, which equals 490.  It has the potential to mean either 490 days or 490 years.  Here it is clear that the Lord intends it to mean years; for this number, in years, is the exact duration that Israel had been rebellious by violating the Sabbath—and  so  God is using the same number of years for determining Israel’s future (most of which is now in the past).  Let me explain this further…

The Sabbath year was every seven years; and so we are saying that Israel was disobedient not only for that Sabbath year…