In Acts 2 God poured out His Spirit upon all flesh, and three thousand were saved (Acts 2:17, 41). But when God pours out the Spirit of grace upon the inhabitants of Jerusalem, many thousands of Israel, even the entire race of Israel alive at that time, will be saved (Rom. 11:26-27). The Spirit of grace here is in contrast to the Spirit of power in Acts 1:8 and Acts 2:1-4. The Spirit of power is to strengthen us, but the Spirit of grace is to bring us into the enjoyment of the Triune God. In Acts 2, at the beginning of the age of grace, the church age, the Spirit was mainly the Spirit of power, but in this verse, at the end, the consummation, of the age of grace, the Spirit will be mainly the Spirit of grace for the enjoyment of the Triune God. The Jews on the day of Pentecost were stubborn and hard; hence, the Spirit of power was poured out to inspire them to repent. But the half of the inhabitants of Jerusalem that survive the attack of Antichrist and his armies (Zech. 14:2) will have lost their taste for everything other than God and will have already repented. Therefore, the Spirit of grace will be poured out upon them so that they can receive the Triune God as their enjoyment.