Joh 7:37-39 In the last day, that great day of the feast, Jesus stood and cried, saying, If any man thirst, let him come unto me, and drink.
He that believeth on me, as the scripture hath said, out of his belly shall flow rivers of living water.
(But this spake he of the Spirit, which they that believe on him should receive: for the Holy Ghost was not yet given; because that Jesus was not yet glorified.)KJV
They that believe on Jesus shall receive the Holy Spirit. The meaning is very easy to see is'nt it? Then why do we get it all confused?
If anyone believes in Jesus Christ with all the heart they shall receive the Holy Spirit. The faith to believe in Jesus comes from God; it is a gift. That faith is received into the heart or spirit of a man and not his head. Head belief in Jesus does not mean you will receive the Holy Spirit. Only genuine faith, which is of the heart of man, will ensure you receive the Holy Spirit.
You can tell it is heart belief and not mental assent because Jesus says If any man thirst...let him come to Me and drink. The thirst Jesus speaks about here is a heart condition. A thirsty heart knows nothing else will satisfy it except the presence of God. A thirsty heart is like a deer panting for the water brooks. A thirsty heart will be filled. In contrast however, the man who only gives mental assent to Jesus will not be filled with the Spirit. A man who only believes mentally that Jesus is God's Son does not thirst. That man's heart has not yet grasped it's need of Jesus; it is still clinging to self righteousness. Only the man who thirsts after Jesus and all He is and has, will receive the Holy Spirit. READ MORE HERE