In his earthly career, Christ Jesus demonstrated the nature and qualities of the original man of God's creating. This man is described in the first chapter of Genesis as made in God's image and likeness, as good, and as having dominion over the lesser creations of God. Since God is Spirit, the original man, whom Jesus revealed and demonstrated, is wholly spiritual.
After Jesus had preached the Sermon on the Mount, setting forth the qualities whereby the original man is manifested in human experience, the people were amazed at the words of wisdom which proceeded out of his mouth. It is recorded (Matt. 7: 29), "He taught them as one having authority, and not as the scribes." And, indeed, his authority came direct from God, by reason of his spiritual origin.
Toward the end of his career, the officers who were ordered to apprehend the Master and bring him to the chief priests and the Pharisees testified (John 7:46), "Never man spake like this man." The eternal truths which the Way-shower uttered were indeed God-inspired, and only those who were spiritually prepared to receive and demonstrate them understood their significance.