What is the significance of Abijah including a covenant of salt with David and his sons?

Question

Then Abijah stood up on Mount Zemaraim that is in the hill country of Ephraim and said, “Hear me, O Jeroboam and all Israel! Ought you not to know that the LORD God of Israel gave the kingship over Israel forever to David and his sons by a covenant of salt?
(2 Chronicles 13:4-5 ESV)

This is the only mention of a "covenant of salt" with respect to David. How is Jeroboam to know the LORD God gave the kingship over Israel to David and his sons, by a covenant of salt? The other reference to a covenant of salt is in Numbers 18 where the LORD God makes a covenant of salt with Aaron:

All the holy contributions that the people of Israel present to the LORD I give to you, and to your sons and daughters with you, as a perpetual due. It is a covenant of salt forever before the LORD for you and for your offspring with you.” (Numbers 18:19 ESV)

When David brought the Ark of the Covenant to Jerusalem, he first built a portable Tabernacle like Moses did, then he acted as Aaron the high priest would:

And they brought in the ark of the LORD and set it in its place, inside the tent that David had pitched for it. And David offered burnt offerings and peace offerings before the LORD. And when David had finished offering the burnt offerings and the peace offerings, he blessed the people in the name of the LORD of hosts. (2 Samuel 6:17-18 ESV)

David offered burnt offerings, peace offerings, then blessed the people as Aaron is instructed (Numbers 6). In summarizing David's leadership over Israel, his sons are called priests:

and Benaiah the son of Jehoiada was over the Cherethites and the Pelethites, and David's sons were priests. (2 Samuuel 8:18 ESV)

In particular, Chronicles describes the extent to which Solomon carried out priestly duties:

Then Solomon offered up burnt offerings to the LORD on the altar of the LORD that he had built before the vestibule. as the duty of each day required, offering according to the commandment of Moses for the Sabbaths, the new moons, and the three annual feasts—the Feast of Unleavened Bread, the Feast of Weeks, and the Feast of Booths. (2 Chronicles 8:12-13 ESV)

The "revised" history in Chronicles describes Solomon functioning as priest for at least one complete annual cycle.

Is Abijah using a covenant of salt to say David and his sons are rightful priests as well as the rightful king?

Answer 1

The phrase "covenant of salt" is likely used as a figure of speech in II Chronicles 13:4-5 to indicate an everlasting covenant rather than as a specific reference to the covenant of Aaron.

The classical commentators suggest that the metaphor "covenant of salt" originated from the well known use of salt as a preservative. See also Leviticus 2:13.

Abijah is apparently referring to the prophecy of Nathan in II Samuel 7:12-15 (NIV)

"The Lord declares to you that the Lord himself will establish a house for you. When your days are over and you rest with your ancestors, I will raise up your offspring to succeed you, your own flesh and blood, and I will establish his kingdom. He is the one who will build a house for my Name, and I will establish the throne of his kingdom forever. I will be his father, and he will be my son. When he does wrong, I will punish him with a rod wielded by men, with floggings inflicted by human hands. But my love will never be taken away from him, as I took it away from Saul, whom I removed from before you. Your house and your kingdom will endure forever before me; your throne will be established forever."

The attempt to connect between the two uses of "covenant of salt" to suggest that Abijah implied that the house of David would be not only kings but priests is without foundation.

The prophecy of Nathan makes no mention of priesthood, only of kingship.

In 2 Chronicles 13:4-5 Abijah makes no reference to priesthood, but later in the same speech, 2 Chronicles 13:9 (ESV), Abihah says:

Have you not driven out the priests of the LORD, the sons of Aaron...?

which shows that Abijah sees the sons of Aaron, not the sons of David, as the rightful priests.

In I Samuel 23:9-11 (ESV), after Abiathar escapes from Saul to Keilah with the ephod (the breastplate on which were mounted twelve precious stones):

David knew that Saul was plotting harm against him. And he said to Abiathar the priest, “Bring the ephod here.” Then David said, “O Lord, the God of Israel, your servant has surely heard that Saul seeks to come to Keilah, to destroy the city on my account. Will the men of Keilah surrender me into his hand?

there is no indication that David himself wore the ephod or even asked the questions himself. Since David was not only not a son of Aaron but was certainly not a high priest, to have worn the such a garment that was worn only by the high priest and worn only with the other accompanying priestly garments would certainly have been noteworthy.

In 2 Samuel 6:17-18 there is no indication that David himself is performing the priestly duties of the sacrifices, only that he has brought the sacrifices, i.e paid for them and accompanied them to the place where they were offered. And the following verse, 19, reads

and distributed among all the people, the whole multitude of Israel, both men and women, a cake of bread, a portion of meat, and a cake of raisins to each one. Then all the people departed, each to his house.

It is unlikely that David himself personally handed out this largesses to the multitudes even though a simple reading of the verse could indicate this. David probably had a large group of administrators and staff who took care of the details.

The ESV translates כהנים in II Samuel 8:18 ESV simply as "priests", while the KJV and others translate "chief rulers" or "chief ministers", an alternate meaning of כהנים that fits the context of the verse. The Targum for II Samuel 8:18 translates כהנים as "רבריבין" - overlords. The parallel verse in I Chronicles 18:17 (ESV) reads

and Benaiah the son of Jehoiada was over the Cherethites and the Pelethites; and David’s sons were the chief officials in the service of the king.

Finally, in II Chronicles 8:12-13 there is no indication that Solomon did anything other than bring the sacrifices, as anyone can do, Israelite or non-Israelite. There is no indication that he performed any part of the of the sacrifice such as receiving the blood or placing parts on the altar or removing the ash from the altar that were reserved for the sons of Aaron.

Throughout the OT, the distinctions between priesthood, civil leadership and prophecy are clearly maintained. There is no indication of an ideal that any of these functions should be combined.

Answer 2

As the OP correctly observes, "covenant of salt" only occurs in the two places listed. Ellicott summs up its function:

By a covenant of salt.—As or after the manner of a covenant of salt, i.e., a firm and unalterable compact (see Numbers 18:19). According to ancient custom, salt was indispensable at formal meals for the ratification of friendship and alliance; and only a “salt treaty “was held to be secure. Salt therefore accompanied sacrifices, as being, in fact, so many renewals of the covenant between man and God. (Leviticus 2:13; Ezekiel 43:24; Leviticus 24:7 in the LXX.)

This is confirmed by the parallel allusion to each covenant being permanent, everlasting and eternal:

• 2 Chron 13:5 is referencing the Davidic or royal covenant which was eternal, 2 Sam 23:5, 1 Kings 9:5, 2 Chron 13:5, Eze 37:25, 26
• Num 19:19 is referencing the Levitical covenant (Lev 1-9, 16, 21-27 , Num 3, 4, 8, 18, 25:10-13, Deut 33:8-11, Neh 13:29, Mal 2:4-8) which was eternal, Lev 24:8, Num 25:10-13, Ps 106:30.

Benson confirms this:

2 Chronicles 13:5. By a covenant of salt — A perpetual covenant. The reason of this mode of expression seems to arise from the preserving nature of salt; which, therefore, was made a symbol of friendship and fidelity. It is most likely, that in all solemn covenants which were confirmed by sacrifice, it was an ancient custom to offer salt with the sacrifice, to denote the faith and perpetuity of the covenant; so that, in this view, a covenant of salt will signify a covenant confirmed by sacrifice. See note on Numbers 18:19.

Answer 3

The final question in the OP asks: "Is Abijah using a covenant of salt to say David and his sons are rightful priests as well as the rightful king?" The answer is "No." The phrase "covenant of salt" signifies a binding, solemn promise between God and David, not an inclusion of David into the priesthood.

Covenant of salt with Aaron

It it true that there was a salt covenant between God and Aaron:

All the holy offerings that the Israelites present to the Lord I have given to you, together with your sons and daughters, as a perpetual due; it is a covenant of salt forever before the Lord for you and your descendants as well. (Num. 18:19)

However this covenant does not refer to Aaron's induction into the priesthood. It describes the permanent nature of the Aaronic priesthood. The Jewish Encyclopedia explains:

Particularly holy and inviolable obligations were designated as "salt covenants." It must be borne in mind that in ancient times, as today among the Arab nomads, a meal taken in company meant temporary association among the members of the company and that a covenant was accompanied by a sacrificial meal.

The consecration of priests is presented in great detail in Leviticus 8-10. Many elements are specified, including bread, oil, flesh, fat, smoke, and blood. Salt is not mentioned in relation to the qualification priesthood or the rite of ordination. Quite the contrary, only descendants of Aaron were allowed to hold this office, and David was a descendant of Judah.

Context of Abijah's comment

King Abijah of Judah (called Abijam in the Books of Kings) was a grandson of King Solomon who was currently engaged in a war against the breakaway Kingdom of Israel, of which Jeroboam was the first king. Reading the quote in context clarifies the issue, which had to do with political power, not the priesthood.

Now there was war between Abijah and Jeroboam. Abijah engaged in battle, having an army of valiant warriors... Then Abijah stood on the slope of Mount Zemaraim that is in the hill country of Ephraim and said, “Listen to me, Jeroboam and all Israel! Do you not know that the Lord God of Israel gave the kingship over Israel forever to David and his sons by a covenant of salt?... And now you think that you can withstand the kingdom of the Lord in the hand of the sons of David, because you are a great multitude and have with you the golden calves that Jeroboam made as gods for you...

Abijah's view of the priesthood

Abijah does invoke the issue of the priesthood. But he does not suggest that the line of David are priests. Quite the contrary, he argues that the existing priests in Jerusalem are legitimate and sufficient, while Jeroboam's priests are not:

Have you not driven out the priests of the Lord, the descendants of Aaron, and the Levites and made priests for yourselves like the peoples of other lands?... But as for us, the Lord is our God, and we have not abandoned him. We have priests ministering to the Lord who are descendants of Aaron and Levites for their service.

It is true that both David and Solomon are portrayed as offering sacrifices to God, which is normally a priestly function. But the clear sense of the OP's quote in context is not related to that. Abijah is explicitly aware of the sole legitimacy of the Aaronic priesthood, which he contrasts with the illegitimate priests of Jeroboam's sanctuary. As a member of the tribe of Judah, he knows he is not qualified for priestly office.

We conclude that King Abijah made no argument that he and his forefathers were to be considered priests. The "covenant of salt" here symbolizes the solemn, permanent promise made by God to David. It refers here to a royal covenant, not a priestly one.