OFFICE OF THE HOLY SPIRIT.
The Holy Ghost was promised to those who obeyed the Gospel. To all who receive it, it bears witness to the truth of the Gospel.
"But when the Comforter is come, whom I will send unto you from the Father, even the Spirit of truth, which proceedeth from the Father, he shall testify of me." (John 15: 26).
"Howbeit when he, the Spirit of truth, is come, he will guide you into all truth." (John 16: 13).
If people receive the Holy Ghost they will be led into all truth, according to the promise of Christ. If they are led into all truth they will be led to understand and believe alike.