What did the cross do to Satan's power over believers?
At the cross, Satan was utterly defeated, and his power over believers was broken. Although he remains alive and well, the work of Christ accomplished reconciliation and defeated sin, so sin is no longer the believer’s overpowering victor. For the benefit of the believer, Satan’s power has been broken by the cross.
Les explains that the 490-year prophecy included finishing transgression, making an end of sins, and making reconciliation for iniquity, all accomplished in the work of the cross. He notes that when Christ died, reconciliation became possible, as Paul brings out in 2 Corinthians chapter 5: “be ye reconciled to God.” Les says we now have the ministry of reconciliation, telling a lost world they have already been reconciled—believe it, and God will reckon you as reconciled. He states that in this prophetic timetable, sin was defeated at the cross, and that is where Satan was utterly defeated. Though Satan is still alive and well, for the benefit of the believer, his power has been broken as a result of the work of the cross.