The fabric upon the which the Bible was penned must be viewed as one garment. The whole Bible coheres and centers around the fact of God’s redemption and restoration of both mankind and the whole of creation.
The book of Revelation is Genesis fulfilled. The entire Bible, in fact, weaves a beautiful story of God’s work in creation and, because of the fall, His subsequent effort to restore His creation.
This is why the Gospel of John begins by quoting Genesis: “In the beginning” (John 1:1). Matthew’s gospel commences with a genealogy (Matt 1:2-17) that clearly serves to identify Jesus with the story of the OT. And why the Gospel of Mark opens with a composite citation (1:2; cf Isa 40:3, Exod 23:20, and Mal 3:1) that clearly intends to identify the coming of John the Baptist as the herald of the coming Christ in terms of the fulfillment of the great promise of the restoration of Israel. And Luke’s opening two chapters contain a plethora of OT citations and allusions.
In each instance, the Gospels are connecting their narratives with the OT story. John, however, takes us one step forward. For, he intends us to not only see Jesus in light of the OT, but also in terms of a new creation. That is, ‘in the beginning’ not only serves to connect the story of Jesus in John with Genesis and the OT, but it is also eschatological—forward looking to the new creation. That is, with the coming of Jesus we have another ‘in the beginning.’
What might this mean for us?
First, it means that in Jesus we have the fulfillment of God's covenant promises (2 Cor 1:20). And we must, therefore, read our Bible's in this light.
Secondly, it means that the 'eschaton' (the end-times) have begun in Jesus. We live in the 'last days'. The 'last days' then are not something to query about as though they are future and distant (or perhaps imminent) and potentially not important. Instead, they are something for us to presently endure.
Finally, the inauguration of the New Creation in Jesus means that our mission as God's people entails the bringing in of the New Creation. We are God's image bearers on earth: and as such we must reign! (of course, reigning in the New Creation is not like the kings of this world (Luke 22:25-30); but entails submission of our very lives to the Kingdom of our Lord (Rev 12:11)).