Concerning the Book of Psalms. That the penman of the Psalms did pretend to speak and write by the inspiration of the Spirit of God as much as the prophets when they wrote their prophecies, the following things do confirm:
1. Singing divine songs was of old one noted effect of the inspiration of the Spirit of God in the prophets, insomuch that such singing was called by the name of prophesying. 1 Samuel 10:5; 1 Samuel 10:6. "Thou shalt meet a company of prophets coming down from the high place, with a psaltery, and a tabret, and a pipe, and a harp before them, and they shall prophesy, and the Spirit of the Lord will come upon thee, and thou shalt prophesy with them." See also 1 Chronicles 25:1-3. This seems to have been the most ancient way of prophesying. Inspired persons of old used to utter themselves in a parable, as sometimes it is called, or a kind of song. Thus it was that Miriam uttered herself when she did the part of a prophetess, Exodus 15:20; Exodus 15:21. "And Miriam, the prophetess, the sister of Aaron, took a timbrel in her hand, and all the women went out after her, with timbrels and with dances, and Miriam answered them, Sing ye to the Lord, for he hath triumphed gloriously, the horse and his rider hath he thrown into the sea." She, in Numbers 12:2, boasts that God had spoken by her as well as by Moses. She seems to have reference to this time, for it does not appear that God ever had spoken by her at any other time, and it is probable that it was from her being inspired at that time (or at least chiefly), that she was called a prophetess. And this was the way that Moses delivered his chief and fullest prophecy concerning the future state of Israel, and the church of God, and the world of mankind, in that song in Deuteronomy 32; the words were all indited by God, as appears by Deuteronomy 31:19; Deuteronomy 31:20; Deuteronomy 31:21. And Moses's blessing of the children of Israel, and his prophecy of their future state, in Deuteronomy 3. is delivered song-wise, which especially appears in the beginning and ending. And so are Balaam's prophecies, or parables. Jacob's blessing and prophecies concerning the future state of the posterity of his twelve sons, Genesis 49. is delivered in a like style, as may be plain to anyone that observes. Zechariah is said to prophesy in uttering a song, Luke 1:67. Singing these very psalms in the sanctuary by the musicians that David appointed, is called prophesying, 1 Chronicles 25:1; 1 Chronicles 25:2; 1 Chronicles 25:3. And Asaph is called a seer, or prophet, and represented as speaking as such in uttering those psalms that he penned, 2 Chronicles 29:30. We are expressly informed of David in an eminent instance, wherein he uttered himself in a remarkable manner as the sweet psalmist of Israel, that he did profess himself to speak by the immediate inspiration of the Spirit of God. 2 Samuel 23:1; 2 Samuel 23:2, etc. "Now these be the last words of David." (And then in what next follows David's words begin, as may be confirmed by comparing them with Numbers 24:3; Numbers 24:4; Numbers 24:15; Numbers 24:16.) "David, the son of Jesse, hath said, and the man who was raised up on high, the anointed of the God of Jacob, and the sweet psalmist of Israel, said: The Spirit of the Lord spake by me, and his word was in my tongue. The God of Israel said, the Rock of Israel spake to me." In its being said that these are the last words of David, it is implied that there had been many other words; that he, as the sweet psalmist of Israel, had uttered many things before; and when David, in these his last words, says, "The Spirit of the Lord spake by me," it must be understood of all these words spoken of in this place, whether mentioned or referred to, all the words that he had uttered as the sweet psalmist of Israel. And there can, perhaps, no other good reason be given why he should be mentioned under that character of the sweet psalmist of Israel here in the introduction of these his last words, rather than all other places of his history, but only because these were the last words that David had uttered as the sweet psalmist of Israel, and as it were the sum of all those preceding records referred to, expressing the main drift and substance of those holy songs he had sung by the inspiration of the Spirit of God all his life-time, and the ultimum, the chief thing, he had in view in those Psalms 4. It is evident that the penman of the Psalms did pretend to speak by a spirit of prophecy, because the psalms are full of prophecies of future events, as Psalms 11:6; Psalms 22:27, to the end. Psalms 37:9; Psalms 37:10; Psalms 37:11; Psalms 60:6; Psalms 60:7; Psalms 60:8; Psalms 64:7, to the end; Psalms 68:31; Psalms 69:34-36; Psalms 72; Psalms 86:9; Psalms 96:13; Psalms 102:13-22; Psalms 108; Psalms 138:4; Psalms 138:5; Psalms 149:7; Psalms 149:8; Psalms 149:9. And many other things in the Psalms are uttered in a prophetical manner and style.
5. It is also most manifest that the penman of the Psalms did pretend to speak by the Spirit, and in the name of the Lord, as the prophets did. By this, that God in the Psalms is very often represented as speaking, and the words are evidently represented as his words, in like manner as in the prophets, as Psalms 14:4; Psalms 50:7-14; Psalms 81:6-16; Psalms 82; Psalms 53:4; Psalms 81; Psalms 87; Psalms 91:14-16; Psalms 95:8-11; Psalms 132:14, to the end; Psalms 45:16, to the end; Psalms 2:6, to the end; Psalms 32:8, to the end; Psalms 60:6-8; Psalms 68:13; Psalms 89:3; Psalms 89:4; Psalms 89:19-37; Psalms 108:7-9; Psalms 110:1-4.
The Book of Psalms. It is a further confirmation of these things, that we find that David very early was endowed with the spirit of prophecy and miracles; he wrought a miracle when he slew the lion and the bear, and acted and spake by that spirit of prophecy when he went forth against Goliath, as is very apparent by the story.
The Book of Psalms. That this is divinely inspired may be further argued from this, that it is every way probable that what are called the songs of Zion, and the Lord's song, in Psalms 137:3; Psalms 137:4. are songs contained in this book. It appears that Zion, or God's church, had sacred songs fancied as such in the world, and that they were properly called the Lord's songs, which argues that they had God for their author, and were consecrated by his authority, as a word being called the word of the Lord, argues it to be a word that came from God, and as a house being called the house of the Lord, signifies its being a house consecrated to God by divine authority. So of the Lord's day, the city of God, the altar of God, etc. etc.
When all the utensils of the temple were exactly, and even in the most minute circumstances, formed by divine direction, it would be strange if the songs of the temple, which are vastly more important and material in the worship of God, should not be formed by divine direction. These were not merely external circumstances of divine worship as the other, but the very matter of the worship. As David was divinely instructed in all the place, and form, and instruments of the temple, and all the new ordinances relating to the attendance and orders of the priests, and the Levites, and the circumstances of their ministration, and particularly of the singers, it would be strange if the songs that they were to sing, the most material and effectual thing of all, should not be of divine appointment, but should be left wholly to human wisdom and invention. (See 1 Chronicles 6:31; 1 Chronicles 16:4-7; 1 Chronicles 23:6; 1 Chronicles 23:25 to the end, and chap. 25 and 28:11, to the end, especially verse 19 and 21.
We have an account that David and Samuel the seer acted jointly in appointing the orders of the porters of the Levites, 1 Chronicles 9:22, and much more the orders of the Levites that were to be singers. It is noted that some of those Levites themselves that were appointed by David as chief musicians, or singers, were seers, or prophets. So of Heman, 1 Chronicles 25:5, and the expressions there lead us, in this verse and the context, to suppose that he acted as a prophet in that matter in assisting David in composing psalms, and appointing the order of singers. Yea, it is expressly said that the order of the singers was appointed by David with the assistance of the prophets, by the commandment of the Lord. 2 Chronicles 29:25. "And he set the Levites in the house of the Lord with cymbals, with psalteries, and with harps, according to the commandment of David, and of Gad the king's seer, and of Nathan the prophet: for so was the commandment of the Lord by his prophets." And Asaph, another of the chief musicians, and penman of many of the psalms, is spoken of as acting as a seer, or prophet, in this matter. Verse 30. "Hezekiah the king commanded the Levites to sing praise unto the Lord, with the words of David and of Asaph the seer." (See the like of Jeduthun, 2 Chronicles 35:15.)