This coming Sunday is the 5th Sunday in Ordinary Time. In yesterday’s post we considered two verses that fall between the Sunday gospel readings that are a caution for any would-be disciple. Today, we consider the well known “salt of the earth” metaphor: “You are the salt of the earth. But if salt loses its taste, with what can it be seasoned? It is no longer good for anything but to be thrown out and trampled underfoot.” (Mt 5:13)
As Boring [Gospel of Matthew, 181] notes, salt had several uses in the ancient world. In the OT, salt was added to sacrifices (Lev 2:13), connected with purity (Ex 30:35; 2 Kgs 2:19–22), symbolic of covenant loyalty (Num 18:19; Ezra 4:14), and used as a seasoning for food (Job 6:6). In the Mishnah salt is associated with wisdom (m. Sotah 9:15). As well, salt was used as a preservative. It is easy to see how all the OT usages of salt would be possible connotations.
The actual Greek is more emphatic than the translation we have in English. The pronoun hymeis (you) is unnecessary. Its presence in the sentence is to give emphasis to what follows. Contextually, it says, “It is you and not those others…” The understanding would not be one of misplaced pride for the hearer, but rather a warning. Salt serves mainly to give flavor, and to prevent corruption. Disciples, if they are true to their calling, make the earth a purer and a more palatable place. But they can do so only as long as they preserve their distinctive character: unsalty salt has no more value.
Jesus was using a proverbial image (it recurs in Bekhoroth 8b). The Rabbis commonly used salt as an image for wisdom (cf. Col. 4:6), which may explain why the Greek word (mōranthē ) represented by lost its taste actually means ‘become foolish.’ A foolish disciple has no influence on the world. (RT France, Matthew: An Introduction and Commentary)
To be a disciple and to have no influence in the world is a contradiction.
Image credit: Cosimo Rosselli Sermone della Montagna, 1481, Sistine Chapel, Public Domain
friarmusings 
The last paragraph in your piece above appears to be drawn from R.T. France’s work in the Tyndale Commentary series, but I don’t see credit given to France in your piece. What drew my eye to this was that what you included above, if I am not mistaken, is an exact quote of France’s work (parenthetical comments and all).
You are correct. Thanks for the note, the post has been updated. These pieces were part of a larger effort from years ago that I try to trim down to manageable sizes – things get lost in editing and trying to scale down – and in some cases perhaps the original had no annotation. But as I note on the blog: ” (The commentaries are hopefully well documented and credit given to the scholars upon whose work I relied. Any failures in this area are my own and were not intentional.)” pa et bonum