Genesis 20:7

He is a prophet, and he shall pray for thee - The word prophet, which we have from the Greek προφητες, and which is compounded of προ, before, and φημι, I speak, means, in its general acceptation, one who speaks of things before they happen, i.e., one who foretells future events. But that this was not the original notion of the word, its use in this place sufficiently proves. Abraham certainly was not a prophet in the present general acceptation of the term, and for the Hebrew נביא nabi, we must seek some other meaning. I have, in a discourse entitled "The Christian Prophet and his Work," proved that the proper ideal meaning of the original word is to pray, entreat, make supplication, etc., and this meaning of it I have justified at large both from its application in this place, and from its pointed use in the case of Saul, mentioned 1 Samuel 10, and from the case of the priests of Baal, 1 Kings 18, where prophesying most undoubtedly means making prayer and supplication. As those who were in habits of intimacy with God by prayer and faith were found the most proper persons to communicate his mind to man, both with respect to the present and the future, hence, נביא nabi, the intercessor, became in process of time the public instructor or preacher, and also the predictor of future events, because to such faithful praying men God revealed the secret of his will. Hence St. Paul, 1 Corinthians 14:3, seems to restrain the word wholly to the interpreting the mind of God to the people, and their instruction in Divine things, for, says he, he that prophesieth speaketh unto men to edification and exhortation and comfort. See the discourse on this text referred to above. The title was also given to men eminent for eloquence and for literary abilities; hence Aaron, because he was the spokesman of Moses to the Egyptian king, was termed נביא nabi, prophet; Exodus 4:16; Exodus 7:1. And Epimenides, a heathen poet, is expressly styled προφητης, a prophet, by St. Paul, Titus 1:12, just as poets in general were termed vates among the Romans, which properly signifies the persons who professed to interpret the will of the gods to their votaries, after prayers and sacrifices duly performed. In Arabic the word naba has nearly the same meaning as in Hebrew, but in the first conjugation it has a meaning which may cast light upon the subject in general. It signifies to itinerate, move from one place or country to another, compelled thereto either by persecution or the command of God; exivit de una regione in aliam - migrans de loco in locum - Golius. Hence Mohammed was called an nabi, because of his sudden removal from Mecca to Medina, when, pretending to a Divine commission, his townsmen sought to take away his life: e Mecca exiens Medinam, unde Muhammed suis Nabi Allah dictus fuit - Golius. If this meaning belonged originally to the Hebrew word, it will apply with great force to the case of Abraham, whose migratory, itinerant kind of life, generally under the immediate direction of God, might have given him the title nabi. However this may be, the term was a title of the highest respectability and honor, both among the He brews and Arabs, and continues so to this day. And from the Hebrews the word, in all the importance and dignity of its meaning, was introduced among the heathens in the προφητης and vates of the Greeks and Romans. See note on the word seer, Genesis 15:1 (note).

Abraham is here designated by the Lord a prophet. This constituted at once the gravity of Abimelek's offence Psalm 105:15, and the ground of his hope of pardon. It is at the same time a step in advance of all the previous spiritual attainments of Abraham. A prophet is God's spokesman, who utters with authority certain of the things of God Exodus 7:1; Exodus 4:15. This implies two things: first, the things of God are known only to him, and therefore must be communicated by him; secondly, the prophet must be enabled of God to announce in correct terms the things made known to him. These things refer not only to the future, but in general to all such matters as fall within the purpose and procedure of God. They may even include things otherwise known or knowable by man, so far as these are necessary to the exposition of the divine will. Now Abraham has heretofore received many communications from God. But this did not constitute him a prophet. It is the divinely-authorized utterance of new truth which raises him to this rank. And Abraham's first exercise in prophecy is not in speaking to men of God, but to God for men. "He shall pray for thee." The prophetic and the priestly offices go together in the father of the faithful. These dignities belong to him, not from any absolute merit, for this he has not, but from his call to be the holder of the promise, and the father of that seed to whom the promises were made.