We have noted that the command is to PREACH the Word by READING the Word from the Church in the wilderness onward. All of the Commands, examples and inferences are to SPEAK the Word which a Disciple of Christ will do without commands: those who sell themselves as able to further expound the world are grouped with bad girls. There is no remote connection between discipleship or learning and PLAYING THE FLUTE defined by the same Chalal word meaning to pollute or prostitute.
Jesus made it clear that HE EXPOUNDING the Biblical text which PROPHESIED OF HIM. He did not preach or sing anything connected to the Jacob-cursed and God-abandoned Levites who were instrumental sorcerers for a not-commanded sacrificial system. Paul in Ephesians 4 demands excising all of the performers because THEY LIE IN WAIT TO DECEIVE.
http://www.piney.com/2.Peter.1.Prophecy ... ation.html
In a parallel to SPEAKING that which is written with the BURNING in the HEART:
One of the facts people ignore or hide is that A Church of Christ is built upon or EDUCATED by the Prophets and Apostles.
Eph. 2:20 And are built upon the foundation of the apostles and prophets, Jesus Christ himself being the chief corner stone;
Eph. 2:21 In whom all the building fitly framed together groweth unto an holy temple in the Lord:
One might wonder why churches with Phds would try to REBUILD on the foundation of the Jacob-Cursed and God-Abandoned Levites who made instrumental noise and not music: their prophesying is defined as soothsaying or sorcery because God turned them over to worship the starry host (missed Acts 7).
The Spirit of Christ (the Rock) defined the Church of Christ in the wilderness. As ekklesia or synagogue its CORE was teaching whatever Word of God which was delivered to them by a HIGHER AUTHORITY.
Christ further defined the future REST or assembly both inclusively and exclusively in the PROPHETS.
We have shown that Jesus made those prophecies more certain because God spoke through Him to validate and "expound the prophecies which spoke of him."
Jesus guided the Apostles into all truth and proved HIS authority by signs and wonders.
Paul said that that cannot be CORRUPTED meaning selling learning wholesale which means adultery when anyone speaks beyond the LOGOS or Regulative Principle.
Private interpretation or further expounding--like all Biblical terms--must be understood as a minimally educated person would understand it. Here are some of the things you CANNOT do and still be a New Testament Christian. If you are doing something excluded by the use of words then maybe you should obey the direct command and example of Jesus: PREACH the Word (only) by READING the WORD.