The Scriptures plainly teach us that the truth about Christ's Gospel may only be understood by a work of the Holy Ghost in the sinner and then in the believer after conversion. The Holy Ghost quickens dead men, and reveals to live hearts the precious things about Christ.
Christ promised He would have the Father send the Holy Ghost to His people as a comforter, His Spirit alongside our spirits to guide and to teach and to correct.
But Christ specially told His disciples, the evening that He was betrayed, that He had many things to say to them but they weren't able to bear them then. Christ promised that the Spirit of Truth would guide us into all things, and would present to Christ's people the truth about Christ that He Himself could not tell us before we were able to bear them!
Seeing Christ's promise about the Holy Ghost fulfilled as the Acts and the Epistles unfold is truly a marvelous sight! There was so much about how Christ would redeem His people that were left unclear at His death.
He promised He would save all who put their trust in Him, but how? He intimated that He would give up His body and blood to save us, but what would that accomplish? He indicated He would take us all to a glorious kingdom, but what would it be like?
All these truths were hidden because we could not bear them until after the Resurrection. But then the Holy Ghost came down and began revealing the glories of redemption, of substitution, of salvation by faith in Christ's finish sacrifice, of His High Priesthood for us, of our Sonship, inheritance, and the glories of Christ's reign forever in the New Jerusalem!
By the Spirit's guidance we discover the love of Christ for us!