For an overview of the life and thought of Jonathan Edwards, you can download a special issue of Christian History here:
https://christianhistoryinstitute.org/magazine/issue/jonathan-edwards-and-the-great-awakening
A good online source for his writings:
http://digitalpuritan.net/jonathan-edwards/
From the Miscellanies:
237. ETERNAL PUNISHMENT.
It seems to me certain that the wicked that are punished by God will continue to hate God all the while they are punished, and that their punishment, instead of humbling them, will stir up their hatred to God and make them blaspheme him. Now it is not probable that their punishment will be either taken off or mitigated whilst they do so, nor that they will cease so to do while their punishment is upon them. Those minds that are so destitute of principles of virtue, will unavoidably dreadfully hate that being that brings so much misery upon them. Therefore, the punishment of the damned will be eternal.
239. SPIRITUAL KNOWLEDGE.
From what has been said under the foregoing head, we learn wherein spiritual knowledge consists. For seeing [that] in order to the knowledge of spiritual things there must be those things in the mind, at least in order to a knowledge anything clear and adequate, sinners must be destitute even of the ideas of
many spiritual and heavenly things and of divine excellencies, because they don't experience them. It's impossible for them so much as to have the idea of faith, trust in God, holy resignation, divine love, Christian charity; because their mind is not possessed of those things, and therefore can't have an idea of the excellencies and beauties of God and Christ, of which those things are the image—he "knows not the things of the Spirit of God" [1 Corinthians 2:14].
There has been great inquiry, what was that urim and thummim that was in the breastplate of the high priest, whereas I think we have it plainly described in Exodus 28:17–21.9 And I don't see that, from anything said in Scripture about it, we have reason to think it any other than those twelve precious stones with the names of the twelve tribes on them. And when it is said in Exodus 28:30, "And thou shalt put in the breastplate of judgment the urim and thummim," it is as if he had said thus, thou [shalt] put in the breastplate the urim and thummim which has been described. The drift of this verse does not seem to be to order anything new, but only to give a name to that which had been before described and to tell the use of it, viz. that Aaron might bear the judgment of the children of Israel upon his heart before the Lord continually; the which seems to me to intend, that the high priest might bear that upon his breast which in God's account and judgment should represent the children of Israel, and should stand for 'em before him upon the heart of the high priest their mediator. Every jewel stood for a tribe, and had the name of that tribe written on it that it stood for. God's people are called his jewels. So Christ bears our judgment; that is, he is our representative in judgment and, as to God's dealings with respect to his law, he stands for us.
The name "urim and thummim" signifies light and perfection; and it being 'tis the plural number, may more properly be rendered "glisterings" (or "brightnesses") and "beauties," because of the charming appearances that the jewels made by their different kinds of glisterings,
and the beautiful proportion of their different colors. (The church that those jewels represented is in Psalms 50:2 called by a name that is much like to this, viz. "the perfection of beauty.") Some say there was an extraordinary brightness given those jewels beyond what was natural to them. That the urim and thummim were not two distinct things in the breastplate appears, because sometimes when they are spoken of, but one of the names are mentioned; it's called urim only, as Numbers 27:21 and 1 Samuel 28:6.
The use of it seems to be much the same with the plate of gold on the miter mentioned in Exodus 28:36, whereon was engraved "holiness to the Lord"; which the high priest was to have on his forehead, that he might bear the iniquity of the children of Israel, and that he might be accepted when he came in before the Lord (as Exodus 28:38). By the urim and thummim he was to bear the judgment of the children of Israel on his heart; by this plate of gold he was to bear the iniquity of the children of Israel on his head.
We find them both mentioned after the same manner, where we have an account of Moses putting the holy garments upon Aaron, as in Leviticus 8:8–9, "And he put the breastplate upon him; and he put in the breastplate the urim and the thummim. And he put the miter upon his head; also upon the miter, even upon his forefront, did he put the golden plate, the holy crown, as the Lord commanded Moses."
That which was properly called the breastplate, was a cloth curiously wrought, doubled (as Exodus 28:15–16), and the urim and thummim was1 the four rows of stones set in it Exodus 28:17–18].
The manner of inquiring of God by it was the priest's appearing with it on before the most holy place, waiting for an answer from off the mercy seat; and when they inquired in the camp there was a tabernacle that the ephod was kept in, made in the resemblance of the tabernacle of the congregation (of which see Prideaux's Connection, Part I, p. 222).2
The urim and thummim, by the beauty and excellency of its
appearance was as proper to obtain acceptance and counsel of God, as incense by the sweetness of its smell was to render their prayers and sacrifices acceptable.
It will [be] objected, that if the urim and thummim were nothing but that plate of gold with the jewels in it, why is it said in Ezra and Nehemiah, that those priests that could not prove their genealogy should not eat of the most holy things till there stood up a priest with urim and thummim (as Ezra 2:63)? for if it had been only gold and jewels they could have gotten them before now.
I answer, so if it had been any other material thing they could have gotten them as well as those jewels. But it seems that being lately returned from captivity they had not yet gotten them; and it's no wonder they should not, in the circumstances they were in.
But it seems by this, that they expected to get them in a short time; which if it had been something that must be immediately given by God, they had not so much reason to expect it, for it seems that God had denied them hitherto.
But if the objection be allowed, all that it can argue is that the urim and thummim was not any material thing, but a power given to the breastplate of foretelling or of obtaining divine responses.
For we can't imagine in reason, that any material thing was expected to be sent down from heaven, to be put into the breastplate; but Leviticus 8:8 proves it was [a] material thing. Therefore, if they had those jewels in the breastplate at that time, the reason of their speaking in this manner must be, because they did not think them worthy the name of urim and thummim till they had such a power given them as3 the former urim and thummim had.
36 ¶ And thou shalt make a plate of pure gold, and grave upon it, like the engravings of a signet, HOLINESS TO THE LORD.
37 And thou shalt put it on a blue lace, that it may be upon the mitre; upon the forefront of the mitre it shall be.
38 And it shall be upon Aaron’s forehead, that Aaron may bear the iniquity of the holy things, which the children of Israel shall hallow in all their holy gifts; and it shall be always upon his forehead, that they may be accepted before the Lord.
(Exodus 28:36–38)