But their minds were made dull, for to this day the same veil remains when the old covenant is read. It has not been removed, because only in Christ is it taken away. Even to this day when Moses is read, a veil covers their hearts. But whenever anyone turns to the Lord, the veil is taken away. There were at least 2,000 years between Adam and Abraham.
Some historical documents add thousands of years to that time.
The time between Abraham and Moses is estimated at 430 to 654 years. It also means that at least the first 11 chapters of Genesis do not fall under the Old Covenant. The New Covenant to the Hebrews pointed to Christ's death as fulfillment of Jeremiah's prophecy. The New Covenant began with the blood-death of Christ. That means most of what happened in the Gospels happened under the Old Covenant.