After Jesus tells His disciples that He is leaving them, He gives them further reassurance. When He departs the Helper (or Paraclete) will come who is the Spirit of Truth. This is none of than the third holy person of the blessed Trinity. We can know that the Holy Spirit is indeed a divine person because He possesses a mind, emotions, and a will. The Holy Spirit thinks and knows (1 Corinthians 2:10). The Holy Spirit can be grieved (Ephesians 4:30). The Spirit intercedes for us (Romans 8:26-27). He makes decisions according to His will (1 Corinthians 12:7-11). And according to our passage and John 15-16 the Holy Spirit comes from the Father and Christ in such a way that is not like a messenger, He is not like an angel; He proceeds forth from God as God. He is spoken about in such a way that gives Him co-equality with God and yet a distinction. The Spirit will not be given to the world, however. He is reserved for those whom love and know Christ and therefore He will be with and in them. Jesus tells them despite the world not being able to see Him after His resurrection, they will. Because He lives again, they and we will live by regeneration. Our new life rises as sure as Christ rose from the dead. And it is at this point after the resurrection and the giving of the Spirit they will finally understand the oneness and triune nature of the Father, the Son, and Holy Spirit. Those whom Christ saves in turn loves Him, and in that love He will disclose Himself to us. By the Spirit, we are truly never left alone. Jesus is always with us.
Judas, the son of James, however doesn't understand and asks why the Messiah would only disclose Himself to them and not to the entire world