On the day of Pentecost all the believers were meeting together in one place. Suddenly, there was a sound from heaven like the roaring of a mighty windstorm, and it filled the house where they were sitting. Then, what looked like flames or tongues of fire appeared and settled on each of them. And everyone present was filled with the Holy Spirit and began speaking in other languages, as the Holy Spirit gave them this ability. 
Acts 2:1-4 NLT

In the last days, God says, I will pour out My Spirit on all people. Your sons and daughters will prophesy, your young men will see visions, your old men will dream dreams. Even on My menservants and maidservants I will pour out My Spirit in those days, and they will prophesy. . . And everyone who calls on the name of the Lord will be saved.’
Acts 2:17-18, 21 BSB

For at one time we too were foolish, disobedient, misled, and enslaved to all sorts of desires and pleasures—living in malice and envy, being hated and hating one another. But when the kindness of God our Savior and His love for mankind appeared, He saved us, not by the righteous deeds we had done, but according to His mercy, through the washing of new birth and renewal by the Holy Spirit. This is the Spirit He poured out on us abundantly through Jesus Christ our Savior, so that, having been justified by His grace, we would become heirs with the hope of eternal life.
Titus 3:3-7 BSB

No one can know a person’s thoughts except that person’s own spirit, and no one can know God’s thoughts except God’s own Spirit. And we have received God’s Spirit (not the world’s spirit), so we can know the wonderful things God has freely given us. When we tell you these things, we do not use words that come from human wisdom. Instead, we speak words given to us by the Spirit, using the Spirit’s words to explain spiritual truths.
1 Corinthians 2:11-13 NLT