Institutes of the Christian Religion (1559) - John Calvin
Book 2 - God the Redeemer
Chapter 15 - To Know the purpose for which Christ was sent by the Father and what He conferred upon us, we must look at Him as prophet, king and priest
Sections 1-2 - Christ as prophet
Section 1 - The need of understanding this doctrine: Scripture applicable to Christ's prophetic office
We can't just know the labels, prophet, priest and king.
We have have to understand what they mean.
God gave Israel prophets all along, so they would always have "doctrine sufficient for salvation."
John 4:25; Isa 55:4; 9:6; 28:29; Jer 32:19; Heb 1:1-2; Dan 9:24.
Section 2 - The meaning of the prophetic office for us
The title Christ, Messiah, pertains to all 3 of these offices, as all were anointed with oil. Isa 61:1-2; Luke 4:18.
His teaching is continued in the Church by the Spirit, where the Gospel is preached. Matt 17:5; Joel 2:28; 1 Cor 1:30; Col 2:3. "The perfect doctrine He has brought has made an end to all prophecies." If it is added on to Christ, it isn't worth knowing or teaching.
"It is not lawful to go beyond the simplicity of the gospel."