Holy Ghost Not Essential to Salvation 

Doctrines of Salvation 1:39; “I have never troubled myself about the Holy Ghost whether he will sometime have a body or not because it is not in any way essential to my salvation. He is a member of the Godhead, with great power and authority, with a most wonderful mission which must be performed by a spirit. This has satisfied me without delving into mysteries that would be of no particular benefit.” – Joseph Fielding Smith

Acts 1:8; “But ye shall receive power, after that the Holy Ghost is come upon you: and ye shall be witnesses unto me both in Jerusalem, and in all Judaea, and in Samaria, and unto the uttermost part of the earth.”

Can you just imagine your pastor telling you this?  Or what about Jesus?  Are these the words of God?  Mr. Smith was a “prophet of God” after all and the Mormon Church has always claimed that whatever they say you can trust him because he’s a prophet. 

So when Jesus was telling His disciples to wait in Jerusalem for the power He was going to give them was it really necessary and a benefit? And if not then how do you explain the passage in John 14 when Jesus told them the Comforter would come to them to discern truth?  Is that necessary?