The Holy of Holies, also known as the Most Holy Place, is the inner room of the Tabernacle (and also the Temple) in which was kept the Ark of the Covenant, the Mercy Seat (Exodus 26:34), Cherubim (Exodus 25:18-22), manna (Exodus 16:33), Aaron’s rod (Numbers 17:10), and a copy of the Ten Commandments (Deuteronomy 31:26). It was the place where blood was sprinkled on the Mercy Seat (the lid on top of the Ark) as atonement for the sins of Israel (Leviticus 16:15-33). The only person allowed to enter the Holy of Holies was the high priest. There was only one high priest at a time, and he could enter only once a year. The Holy of Holies measured 20 cubits by 20 cubits by 20 cubits (a cubit is approximately 18-21 inches, so 15 feet square). It was the final room the high priest would enter after he passed the veil, which separated the Holy of Holies from the Holy Place. The Holy of Holies is mentioned many times in the Bible. That was the old covenant.
The Book of Hebrews tells of the finished covenant, the completed high priest, sacrifice and promises.
“Therefore, it was necessary for him to be made in every respect like us, his brothers and sisters, so that he could be our merciful and faithful High Priest before God. Then he could offer a sacrifice that would take away the sins of the people. (2:17)
“Didn’t I tell you that if you believe, you would see the glory of God?” Jesus