“…but now, once at the end of the ages, He has appeared to put away sin by the sacrifice of Himself” (Hebrews 9:26).
The Bible is a book of God’s progressive revelation of Himself and His eternal purpose of salvation in Christ. It begins with God at various times and in various ways communicating to the patriarchs, then through Moses and the prophets. It concludes with His revelation of His final testament by His Son and His apostles and prophets.
The period of human history when God was communicating His will to the fathers is called the Patriarchal Age/Dispensation. The period of human history when God communicated His will to Israel via the Law given to Moses is called the Mosaic Age/Dispensation. Both of these ages/dispensations ended at Calvary, because the giver of God’s final dispensation died and a testament is not in force until after the testator’s death (Hebrews 9:17). Therefore, Christ’s covenant/God’s new testament was the goal, the fulfillment (“the end”) of the ages.
His final dispensation—“these last days (Hebrews 1:2)—is the terminal point of divine revelation. The faith which all must believe and obey to be saved has been given once-for-all-time (Jude 3). Everything God promised to do to save humanity and everything humanity needs to know and do to be saved can only be found in the twenty-seven books of the New Testament.