THE DIVINITY OF THE HOLY SPIRIT
St. Peter said that to lie to the Holy Spirit means to lie to God (Acts 5:4), and since He is the Spirit of God and the Spirit of the Lord, so He is God (Job 33:4, 2 Cor. 3:3; Isa. 61:1).
This Comforter, the Holy Spirit descended and came upon the Apostles in the Day of Pentecost (Acts 2:1-4). He is the One, God promised to send in the book of Joel, “I will pour out My Spirit on all flesh; Your sons and your daughters shall prophesy, Your old men shall dream dreams, Your young men shall see visions” (Joel 2:28-32), and St. Peter mentioned that this prophecy was fulfilled in the Day of Pentecost (Acts 2:16, 17).
He is the Spirit of God and the Spirit of His Son as well (Gal. 4:6), “the Spirit of Christ” (1 Peter 1:11). He is also the “Spirit of Truth” (Jn. 14:17), “When He, the Spirit of Truth, has come, He will guide you into all truth…” (Jn. 16:13).