Now, listen. After the Apostle Paul takes these Hebrews to task in the closing verses of chapter five, calling them babes in Christ when they should have been teachers, he goes on in chapter six to say they're believing the principles of the doctrine of Christ. Let us go on to perfection. Now, I just want to go over this again, in order that this might be fixed in your mind. These things that they were to leave were the shadows of Judaism, the shadows of a temple. They were the principles of the doctrine of Christ. That is, the doctrine of Christ, that great doctrine of salvation, that great doctrine of justification, that doctrine of sins forgiven, and the doctrine of the priesthood of the Lord Jesus Christ was all there taught in those shadows.
Biola Radio Hour; Hebrews 6
Talbot, Louis T., "Hebrews 6" (1958). 1950-1959. mp3 291.