“He will give you another paraclete, that he may be with you for ever, even the Spirit of truth, whom the world cannot receive for it neither sees him in such a way as to recognise him, nor does it know him. You know him, for he dwells with you and will be in you.”
So when Jesus goes He will be replaced with another Who will perform the functions for the disciples that He has performed, One Who is sent by the Father. The word ‘another' means ‘another of the same kind'. And this One will be permanently with them. He will never leave them. For He will be with them for ever. And they will know Him and recognise Him, for He will be with them as a constant companion, and He will indeed be in them. He will be the closest friend and helper anyone could ever have. And He is the Spirit of truth. This idea will be amplified later.
Note that the world cannot receive this Helper. It neither recognises Him nor knows Him. The suggestion of a general activity of the Spirit in world movements is not what Jesus teaches, nor is it the general teaching of Scripture. The Spirit works through His own. Here the world is in contrast to the people of God. The one is outside His kingdom. The other are His kingdom. The Kingly Rule of God is with them and among them, and with and among them alone.
“You know Him, for He dwells with you and will be in you.” ‘Dwells with you' here refers to Jesus Himself in His Spirit-filled, Spirit revealing life. ‘Dwells in you' stresses that instead of having an outward knowledge of Him, they will have a deeper inward knowledge through His indwelling Spirit. Thus do they know Him now. So will they know Him in the future.