Baptism (Holy Spirit)

Matt 3:11
I indeed baptize you with water unto repentance, but He who is coming after me is mightier than I, whose sandals I am not worthy to carry. He will baptize you with the Holy Spirit and fire.
NKJV

Acts 19:5-6
When they heard this, they were baptized in the name of the Lord Jesus. 6 And when Paul had laid hands on them, the Holy Spirit came upon them, and they spoke with tongues and prophesied.
NKJV

Acts 8:14-17
Now when the apostles who were at Jerusalem heard that Samaria had received the word of God, they sent Peter and John to them, 15 who, when they had come down, prayed for them that they might receive the Holy Spirit. 16 For as yet He had fallen upon none of them. They had only been baptized in the name of the Lord Jesus. 17 Then they laid hands on them, and they received the Holy Spirit.
NKJV

Titus 3:5
He saved us, through the washing of regeneration and renewing of the Holy Spirit
NKJV

Many people who have not experienced the Baptism of the Holy Spirit might "question" it. I did until I finally experienced it for myself. I did not start speaking in tongues when I was prayed for, but I did hear God speak to me that night, and have since experienced many "different" encounters with the Holy Spirit.