Theologians use the term "inaugurated eschatology." That can be confusing because the word eschatology can have various meanings. It can mean the events associated with the second coming of Christ. But it's used more broadly with respect to Old Testament prophecies of a coming great day of salvation. The Old Testament says, "In the last days it shall be" and then describes God's coming to save his people in a definitive way. Well, Hebrews 1 picks up that Old Testament usage and talks about the fact in the last days God has spoken to us in the Son. In other words, Hebrews is pointing out that those last days that the Old Testament prophets prophesied have already begun to come to past. Christ has come. His reign of salvation has begun. Now, the term inaugurated eschatology means that you've got a fulfillment that's already in progress. Christ brought that fulfillment; his death and resurrection were a great climactic events that brought in the salvation of God in a definitive way. It's inaugurated but it's not complete, because we're still waiting for the second coming. So, you'll find language in the New Testament that's used both with respect to now and with respect to the future. For instance, we have eternal life now. Jesus says, "Whoever believes in me has eternal life," but he also talks about eternal life as something future, that is, that will have when we have resurrected bodies. Well, which is true? Both are true because God's salvation is worked out in two stages. This is the inaugural stage, ever since the first coming of Christ, and the consummate stage is when Christ returns.