The Day of Pentecost

Acts chapter 2 tells of the day that the Lord's church was empowered by the Holy Spirit of God. Yes, the church existed prior to this day. But since the ascension of the Lord Jesus into glory, and as evidence of His real presence with the Heavenly Father there, the Holy Spirit was sent to specially inhabit this church, His church, the church that He built during His earthly ministry, until He returns.