[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 27 at Joh 14:17: Jesus' statement here that the world cannot receive the Holy Spirit is very important. This means that until people are born again (see note 2 at Joh 3:3), they cannot receive the Holy Spirit. Unbelievers cannot receive the baptism of the Holy Spirit (see note 28 at this verse). Peter used this as a proof of salvation in Ac 11:15-17.
Note 28 at Joh 14:17: People, apart from the quickening of the Holy Spirit, cannot believe what they cannot see. Paul said in 1Co 2:14, "But the natural man receiveth not the things of the Spirit of God: for they are foolishness unto him: neither can he know them, because they are spiritually discerned." This is why lost people cannot receive the Holy Spirit (see note 27 at this verse).
Note 29 at Joh 14:17: Jesus made a clear distinction between the Holy Spirit being with the disciples and being in them. The ministry of the Holy Spirit is always involved in all of God's dealings with man (see note 28 at this verse). This was certainly true of the Lord's revelation to the disciples of who Jesus was. However, the Holy Spirit had only so far been with them, but He would soon be in them.
Likewise today, some may claim that they have the Holy Spirit because of the fact that no one can come to Jesus except through the ministry of the Holy Spirit (Joh 6:44). But only through the baptism of the Holy Spirit does He actually come and live in the hearts of the believers.