How does the believer "be to me a son?" When a believer reciprocates the love that comes from the father back to the father in the same manner and quality it was received it is being a son or daughter to the father. When the son learns to rest in the same rest in which our father rest then he or she is being a son to the father. When the believer receives the peace that comes from the father and is at peace with him or herself and with the father this is being a son to him. When our father sees his sons at rest in the peace that he has given them then the sons are being sons to the father. To reiterate: all that our father wants is for his sons to be sons to him. If they attempt to be something other then sons to him the result will be heart rendering to our father to say the least. This is why believers can never be a "prophets" to others and please him who is father. Our father has no pleasure in prophets but His pleasure is only in His sons. Born-again believers can never function in the capacity of a "priest" because this is something much less than being to him a son. Believers can never be a "king" to others for him who is Father because he only wants sons who are " The brightness of his glory, and express image of his person, Hebrews 1:3. When he looks at his son's whom he birthed through "Christ in you" he does not want to see how well his sons function as prophets, priests, Kings, etc. All he wants is to see how they function as sons to Him.