In discussing the Two Ages (as in for instance Jesus' words in Matthew 12:32, "either in this age or in the age to come."), Frame notes that the "age to come" is the age of fulfillment and in some sense occurs after our death and God's final judgment.
He goes on, "But the remarkable thing about NT teaching, in contrast with the Jewish conception, is that in one sense the "age to come" has already appeared in Christ. Believers in Christ are those "on whom the end of the ages has come" (1 Cor 10:11). The closing of the holy places in the temple to worshipers is symbolic of the present age, so that when the veil is torn and we enter boldly into God's presence through Christ, another age has begun (Heb 9:8-9). Christ "has appeared once for all at the end of the ages to put away sin by the sacrifice of himself" (9:26). For believers, then, the "coming age" has begun in Christ. He has dealt with sin once for all." - Frame, ST, p89.