English Standard Version (ESV)
There aren't really two halves to the Bible. It's one story, rooted in what God has done in the Old Testament, where so many promises are made that come to fulfillment in the New Testament. It's one story, about a God seeking to redeem his people, about a God who loves people without limit and will do whatever it takes to redeem his people. It starts in darkness, with God hovering over the face of the deep, and it ends in light, with God himself as our light, having fully completed the redemption from sin and death.
And so Paul reminds those who are listening - he is merely living into the fulfillment of the promises. He hasn't started something new. The first Christians didn't see themselves as starting a new religion -- they saw themselves as blessed because they were seeing the fulfillment of the OT promises. Many of the Jewish leaders were so caught up in history that they stopped paying attention to what God was doing then and there, but Paul was awakened, and so many others were as well, by the power of the Holy Spirit.
So you are a part of an old, old story, and we have the benefit of history, of seeing how God has fulfilled promises. So let us be a people of hope, living into a new and exciting future where God is on the move, alive and dynamically at work in the world, calling us deeper into the old story, to discover what new things God has in store for us today!