Contrast with General Revelation.
God reveals Himself through miraculous means, in physical and vocal appearances, dreams, visions, the written Word, and Jesus Christ. (https://www.gotquestions.org/general-special-revelation.html)
The Bible more clearly confronts our spiritually rebellious race with the reality and authority of God. The character and will of God, the meaning of human existence, the nature of the spiritual realm, and the purposes of God for human beings in all ages are stated in propositionally intelligible form. The Bible publishes in objective form the criteria by which God judges individuals and nations, and the means of moral recovery and restoration to personal fellowship with Him.
(The Origin of the Bible: Newly Updated by F. F. Bruce, J. I. Packer, Philip W. Comfort, and Carl F. H. Henry, 2020. The Authority of the Bible by Carl F.H. Henry. Page 16)
Intelligible Communication
For evangelical orthodoxy, if God's revelational disclosure to chosen prophets and apostles is to be considered meaningful and true, it must be given not merely in isolated concepts capable of diverse meanings but in sentences or propositions. A proposition--a subject, predicate, and connecting verb (copula)--constitutes the minimal logical unit of intelligible communication. "Thus saith the Lord" was an Old Testament prophetic formula that characteristically introduced propositionally disclosed truth, while Jesus employed "But I say unto you" to introduce logically formed sentences that He represented as the veritable word or doctrine of God.
(The Origin of the Bible: Newly Updated by F. F. Bruce, J. I. Packer, Philip W. Comfort, and Carl F. H. Henry, 2020. The Authority of the Bible by Carl F. H. Henry, Page 19-20.)