The Holy Spirit teaches us that the old system was unable to provide a way of access to God because the holiest of all—the Holy of Holies—was limited to the High Priest. This was true as long as the old Levitical system was in existence. There were other exclusions too. The Outer Court separated Gentiles from Jews; The Inner Court separated non-Levites from Levites; The Holy Place separated non-priest from priest; and The Holy of Holies separated the High Priest from all common priests.
The old system was merely a model or type for the time present; it was simply a historical type of something used as an illustration for the present generation.The final sacrifice came with the establishment of the New Covenant. With the New Covenant, the time of reformation arrived. The Messiah serves in a better sanctuary—the one in Heaven not on earth. The one in Heaven was the original one; the earthly Tabernacle was only a copy. That is why Jesus is superior to Aaron.