Contained within the Ark of the Covenant were the pot of manna, Aaron’s Rod and the Tablets of the Covenant (Heb 9:4). The Ark was made of shittim wood and covered with gold. The gold lid was the kapporet, which English translations tend to render as the ‘Mercy Seat’. The Greek term used to translate kapporet in the Septuagint (LXX) is hilasterion – the same word we find in Chapter 3 of Paul’s Letter to the Romans:
…for all have sinned and fall short of the glory of God, being justified freely by His grace through the redemption that is in Christ Jesus, whom God set forth as a propitiation [hilasterion] by His blood, through faith, to demonstrate His righteousness . . .
(Rom 3:23-25 NKJV)
The Ark, like so many other things in the Tanakh (aka the ‘Old Testament’), is a picture of the Messiah. It is he who is the sacrifice whose bleood was sprinkled on the mercy seat, his cross. The gold covering of the Ark speaks of his immortality and the wood pictures his humanity. Messiah is the d’var elohim – the Word of God – made flesh. The manna was in the Ark because Messiah is the bread from heaven. Aaron’s rod that budded was in the Ark because Messiah is the resurrection and the life. The tablets were in the Ark because Messiah is the Torah incarnate.
The Ark went two thousand cubits ahead of the people across the Jordan (Josh 3:3-4). Messiah preceded his people into the olam haba – the Age to Come – by about two thousand years.