Who is the Holy Spirit?

The Holy Spirit is The Comforter that Jesus told us about in the Bible.
KJV John 14:
12 Verily, verily, I say unto you, He that believeth on me, the works that I do shall he do also; and greater works than these shall he do; because I go unto my Father.
13 And whatsoever ye shall ask in my name, that will I do, that the Father may be glorified in the Son.
14 If ye shall ask any thing in my name, I will do it.
15 If ye love me, keep my commandments.
16 And I will pray the Father, and he shall give you another Comforter, that he may abide with you for ever;
17 Even the Spirit of truth; whom the world cannot receive, because it seeth him not, neither knoweth him: but ye know him; for he dwelleth with you, and shall be in you.

Note: In this 17th verse, we are told so much about the Holy Spirit by Jesus. We are told that

1. He IS the Spirit of TRUTH.

2. The World cannot receive him because they do not recognize him, nor do they know him.

3.We are told that WE know him and he dwells (lives) inside of us, and shall be in us.

Now, let's go on to verse 18:
18 I will not leave you comfort less: I will come to you.

How could it be possible that Jesus, whom they would crucify on the cross for the sins of mankind would come to us?

The way in which Jesus would be able to come to us would be through the Holy Spirit *The Comforter*
The Holy Spirit will glorify Jesus and will show us all things that pertain/concern us from the Father God...
14 He shall glorify me: for he shall receive of mine, and shall show it unto you.

15 All things that the Father hath are mine: therefore said I, that he shall take of mine, and shall shew it unto you.

Note:There is a spiritual realm and there is a natural realm. Depending on where we are in our relationship with God, sometimes it would seem that God is truly speaking to our Spirits (not audibly usually) but instead it is that "Still small voice" that I know has come from God the Holy Spirit.

The Comforter will cause us to remember what Jesus has said to us through his word:
John 14
25 These things have I spoken unto you, being yet present with you.
26 But the Comforter, which is the Holy Ghost, whom the Father will send in my name, he shall teach you all things, and bring all things to your remembrance, whatsoever I have said unto you.
The Holy Spirit also will show us things to come.
John 16:
13 Howbeit when he, the Spirit of truth, is come, he will guide you into all truth: for he shall not speak of himself; but whatsoever he shall hear, that shall he speak: and he will shew you things to come.
The Holy Spirit reveals things...
Ephesians 3:5
Which in other ages was not made known unto the sons of men, as it is now revealed unto his holy apostles and prophets by the Spirit;

Note: Through his Spirit, we know what he has said to us through his word. The Word of God is the primary source of knowledge from God. His word is truth and life. This is why it is so important not to place credence on what other's say if it runs contrary to the Word, even if they are those in authority in the church, but we must study God's word, go to the source so to speak.

We are sealed with the Holy Spirit when we become born again.

The Holy Spirit will tell us of Jesus and will always point to Jesus and not to himself, as in to be glorified, etc. because the Holy Spirit is the Very Spirit of Jesus!:
26 But when the Comforter is come, whom I will send unto you from the Father, even the Spirit of truth, which proceedeth from the Father, he shall testify of me:

27 And ye also shall bear witness, because ye have been with me from the beginning.
John 15:
Jesus said this about the Comforter, which is the Holy Spirit:
John 14:
22 Judas saith unto him, not Iscariot, Lord, how is it that thou wilt manifest thyself unto us, and not unto the world?
23 Jesus answered and said unto him, If a man love me, he will keep my words: and my Father will love him, and we will come unto him, and make our abode with him.
Note: How would Jesus and his Father come to you and make their home with you? They are in Heaven.

But they can, they come in the form of the Holy Spirit and the way that they can and do live Inside of your hearts is by and through the Holy Spirit.

If I do not go, the Spirit will not come
Jesus said that if he did not go away, (Go to be with our Father) the Comforter would not come...
John 16:
7 Nevertheless I tell you the truth; It is expedient for you that I go away: for if I go not away, the Comforter will not come unto you; but if I depart, I will send him unto you.
He will guide us into ALL truth...
John 16:
.12 I have yet many things to say unto you, but ye cannot bear them now.
13 Howbeit when he, the Spirit of truth, is come, he will guide you into all truth: for he shall not speak of himself; but whatsoever he shall hear, that shall he speak: and he will shew you things to come.
After we are born again, we are SEALED with the Spirit
Ephesians
13 In whom ye also trusted, after that ye heard the word of truth, the gospel of your salvation: in whom also after that ye believed, ye were sealed with that holy Spirit of promise,
14 Which is the earnest of our inheritance until the redemption of the purchased possession, unto the praise of his glory.

Attributes of the Holy Spirit:
We see that we can grieve the Holy Spirit:

Ephesians 4:
30 And grieve not the holy Spirit of God, whereby ye are sealed unto the day of redemption.
31 Let all bitterness, and wrath, and anger, and clamour, and evil speaking, be put away from you, with all malice:
32 And be ye kind one to another, tenderhearted, forgiving one another, even as God for Christ's sake hath forgiven you.

How can we receive the Holy Spirit?
Luke 11:
13. If ye then, being evil, know how to give good gifts unto your children: how much more shall your heavenly Father give the Holy Spirit to them that ask him? (Much more in depth about this question later)

The Holy Spirit and Daniel in the Old Testament

Do you know that it was the Holy Spirit that revealed to Daniel what Nebuchadnezzar's dream was along with the interpretation? If the Holy Spirit had not showed this to Daniel, him and the rest of the wise men in Babylon would have been put to death because the decree had already been made by the King!
Daniel 2:5 The king answered and said to the Chaldeans, The thing is gone from me: if ye will not make known unto me the dream, with the interpretation thereof, ye shall be cut in pieces, and your houses shall be made a dunghill.
But what happened later?
Daniel prayed:

15 He answered and said to Arioch the king's captain, Why is the decree so hasty from the king? Then Arioch made the thing known to Daniel.
16 Then Daniel went in, and desired of the king that he would give him time, and that he would shew the king the interpretation.
17 Then Daniel went to his house, and made the thing known to Hananiah, Mishael, and Azariah, his companions:
18 That they would desire mercies of the God of heaven concerning this secret; that Daniel and his fellows should not perish with the rest of the wise men of Babylon.
19 Then was the secret revealed unto Daniel in a night vision. Then Daniel blessed the God of heaven.
20 Daniel answered and said, Blessed be the name of God for ever and ever: for wisdom and might are his:
21 And he changeth the times and the seasons: he removeth kings, and setteth up kings: he giveth wisdom unto the wise, and knowledge to them that know understanding:
22 He revealeth the deep and secret things: he knoweth what is in the darkness, and the light dwelleth with him.
23 I thank thee, and praise thee, O thou God of my fathers, who hast given me wisdom and might, and hast made known unto me now what we desired of thee: for thou hast now made known unto us the king's matter.

So the Holy Spirit gave insight to Daniel both about the Dream and the interpretation of the King's dream.
24 Therefore Daniel went in unto Arioch, whom the king had ordained to destroy the wise men of Babylon: he went and said thus unto him; Destroy not the wise men of Babylon: bring me in before the king, and I will shew unto the king the interpretation.
25 Then Arioch brought in Daniel before the king in haste, and said thus unto him, I have found a man of the captives of Judah, that will make known unto the king the interpretation.
26 The king answered and said to Daniel, whose name was Belteshazzar, Art thou able to make known unto me the dream which I have seen, and the interpretation thereof?
27 Daniel answered in the presence of the king, and said, The secret which the king hath demanded cannot the wise men, the astrologers, the magicians, the soothsayers, shew unto the king;
28 But there is a God in heaven that revealeth secrets, and maketh known to the king Nebuchadnezzar what shall be in the latter days. Thy dream, and the visions of thy head upon thy bed, are these;
29 As for thee, O king, thy thoughts came into thy mind upon thy bed, what should come to pass hereafter: and he that revealeth secrets maketh known to thee what shall come to pass.

There are so many instances in which the Holy Spirit has revealed
knowledge and wisdom to people. And he will reveal the things of God to us just as he did to Daniel if we are dedicated to him and if we will listen.