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Until then, the gospel reveals that power and salvation of that “still coming” DAY has come in unexpected advance of THAT DAY through the revelation of the secret hidden in other ages (Ro 16:25-26; Eph 6:19; 1Pet 1:11). But according to Paul, this present fulfillment of the covenant through the revelation of the mystery of the gospel and gift of the Spirit cannot stop short of the grafting of the natural branches back into their own place. Paul does not present their return as a generous divine initiative tacked on at the end of the age for good measure. No, it is a covenant necessity demanded by the specific language of the covenant, (Ro 11:26-29), which would only be established with the larger nation at the post-tribulational day of the Lord. That is the eschatology of the OT, which the revelation of the mystery modifies, but does NOT erase. The day of the Lord will bring all that the literal reading of scripture said it will bring.
So I see Peter as saying “this is that,” but this is NOT “all” of that. It is indeed the Spirit promised to Israel in association with the well known day of the Lord. The promise of that day has arrived. It is here. But the day itself, and the full balance that remains to be fulfilled at that time remains for a post-tribulational future. Nothing about that has changed. The powers of the age to come have indeed broken decisively into this present evil prior to and apart from the kind of outward transformation expected in association with the day of the Lord. This, however, does nothing to change all that Scripture promises will come to the broken and penitent remnant that will look upon Him whom they pierced (Zech 12:10), when “that generation” will say with one voice, “blessed is He that cometh in the name of the Lord” (Mt 23:39). Hallelujah!
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