the question is more whether the scriptures were ever intended as a means unto themselves to lead folks to God.
if you read Holy Scripture God has always favored a priesthood for the purpose of bringing people to the message Scripture contains.
This simple truth is the power of the Gospel, that you and I are called to tell others of His love and Grace, so that the Holy Spirit may minister to their hearts and call them forth to be born again. I know from the witness of others that the scriptures have the power to open the heart to the Holy Spirit. I also know from my own experience that the witness of Christ in the lives of others brings people to the Savior. To call that the work of a priesthood now is to miss the essence of Salvation. To maintain a healthy relationship with The Lord, we are admonished to gather together under the leadership of 'bishops' and 'priests', else Paul would not have given instruction as to the character nature required for these posts in the Church of believers.
The scriptures may indeed prepare the heart, but the 'leading others to The Lord' is the essence of why Jesus gave the story of the cursed fig tree. The simplicity of the Grace in Christ shows God to be most powerful on our behalf. To them who are perishing, this simple Gospel is foolishness.