Acts 2:1 And as the day of Pentecost was being fulfilled, they were all together in the same place. (4) And they were all filled with the Holy Spirit... Gal 3:14 In order that the blessing of Abraham might come to the Gentiles in Christ Jesus, that we might receive the promise of the Spirit through faith.
Pentecost was the fulfillment of the feast of Weeks, and this feast was also called the feast of Harvest (Exo. 23:16). On that day there was the outpouring of the all- inclusive Spirit.
This Spirit is the rich produce of the processed Triune God given by Him to His chosen people as the blessing of the gospel. Galatians 3:14 indicates that the unique blessing of the gospel is not heaven or even the forgiveness of sins; the unique blessing of the gospel is the Spirit, even the all- inclusive Spirit of the processed Triune God.
This Spirit as the blessing of the gospel is given to us so that we may enjoy the all-inclusive Christ, who is the embodiment of the Triune God, as our good land. The feast of Harvest typifies the enjoyment of the rich produce brought in by the resurrected Christ. This rich produce is the all-inclusive Spirit of the processed Triune God given by Him to His chosen people as the blessing of the gospel so that they may enjoy the all-inclusive Christ (the very embodiment of the Triune God) as their good land.
This signifies that the believers, through receiving the bountiful Spirit on the day of Pentecost, not only have entered into the good land, but also have participated in the bountiful riches of the all-inclusive Christ in His resurrection and ascension as God's full allotment in His New Testament economy.