A Prophet. The Hebrew word so rendered ( נָבִיא) is a derivative from a verb ( נָבָא), which signifies to tell, to announce; hence the primary concept of the word is that of announcer, or forth-speaker; and to this the word "prophet" (Greek προφήτης from πρόφημι, I speak before or in place of) closely corresponds; the prophet is one who speaks in the place of God, who conveys God's word to men, who is an interpreter of God to men.
(As illustrative of the meaning of the word, cf. Exodus 7:1; Exodus 4:16.) Hence Abraham is called a prophet (Genesis 20:7), and the term is applied to the patriarchs generally (Psalms 105:15); God conveyed his mind to them, and they spoke it forth to others (cf.
Amos 3:7). Like unto me. When the people heard the voice of God speaking to them at Sinai, and from the midst of the fire uttering to them the Ten Words, they were struck with terror, and besought that they might not again hear that awful voice, but that Moses might act as mediator between God and them—might hear what God should say, and speak it unto them (Deuteronomy 5:22-27).
Moses thus became God's prophet to the people; and of this he reminds them here, as well as of the circumstances amid which he entered specially on this office (cf. Deuteronomy 18:16, Deuteronomy 18:17).
The phrase, "like unto me," does not necessarily imply that the prophet who was to come after Moses was to be in every respect the same as he; all that is indicated is that he would act as Moses had acted as a mediator between God and the people in the way of conveying his will to them.