“But the Comforter, which is the Holy Ghost, whom the Father will send in my name, he shall teach you all things, and bring all things to your remembrance, whatsoever I have said unto you.”
King James Version (KJV)
14:26 In my name - For my sake, in my room, and as my agent. He will teach you all things - Necessary for you to know. Here is a clear promise to the apostles, and their successors in the faith, that the Holy Ghost will teach them all that truth which is needful for their salvation.
Joh 14:26 The Comforter, [which is] the Holy Ghost. More correctly, Holy Spirit. He shall teach you all things. A special promise to the apostles, which fitted them to preach the Gospel authoritatively and leave behind them the records of the New Testament.