In a post at First Things, called “Salt of the Earth” Peter Leithart challenges Christians to consider the negative metaphorical implications of Jesus’ saying. Was Jesus, in fact, pronouncing judgment on a sinful world through saying, “You are the salt of the earth” (Matthew 5:13)?
First of all, he notes what many have observed: that Jesus is not setting his disciples in the context of the “earth,” per se, but in the “land” — he is addressing his Jewish audience and calling those who follow him, “the salt of the land.” Leithart suggests that this brings out the judgmental imagery of salt. They are not salt on food. They are not salt which is added to a sacrifice. They are salt on the land. He then reminds us that this brings with it more threat than promise.
Yahweh’s destruction of Sodom and Gomorrah left behind a proverbial wasteland of salt. When Israel broke covenant, Moses warned that the Lord would make the land “brimstone and salt, a burning waste, unsown and unproductive, and no grass grows on it, like the overthrow of Sodom and Gomorrah, Admah and Zeboiim” (Deut. 29:23; cf. Ps. 107:34). Salting farmland was a tactic of war, a way of cutting off an enemy’s food supplies. Abimelech sealed his victory over the city of Shechem by sowing it with salt (Judg. 9:45), and the Romans salted Palestine during the Jewish War of the late 60s a.d.
Jesus wishes to cast fire to the earth (Lk. 12:49), and his disciples fulfill that desire. When he scatters his salty disciples, the world becomes a wasteland.
The saltiness of the disciples is embodied through a “redemptive righteousness that unravels cycles of sin.” Salt is a metaphor for righteous judgment, then, that would come upon self-righteous Israel, and by extension to the whole world in which Jesus’ disciples live. Though Peter Leithart universalizes this, suggesting that it speaks directly to Christians and their place in the world, it is more likely that Jesus had the immediate present and future in mind and was speaking to the role of his disciples as they accompanied him and proclaimed the Kingdom to Israel. Its application is secondary to Christians today. As Scot McKnight notes in his commentary on the Sermon on the Mount
Also, it is not clear to me that the “judgment” aspect of this metaphor is as much in view as Leithart says. While correct in clarifying Jesus’ saying as, “You are the salt of the land,” Leithart goes too far in suggesting that Jesus is saying the disciples are “salt on the land.” The specific wording and context suggests that their salt ministry occurs “in” the land and is “for the benefit of” the land, just as the “light” in the second Similitude is designed to cast back the darkness and bring glory to God.
Metaphors are both gifts and temptations for preachers. Used well, they draw our hearers into realms where we may imagine the Kingdom and receive the shoes that will enable us to traverse its paths with vigor and stamina. But metaphors are susceptible to over-interpretation, to what my teachers in seminary used to call “illegitimate totality transfer.” That is, when we expound a metaphor, we often try to unpack too much from it, assuming that Jesus must have meant for us to think about every possible meaning for that image. The metaphor of “salt” is capable of evoking its preservative properties, its ability to enhance flavor, its necessity for life and well being, its use in rituals of hospitality, its use in Hebrew sacrifices, and, as Peter Leithart has pointed out, its use in laying waste farmland and bringing destruction upon one’s enemies. I have heard preachers (including myself) expound all of these meanings and suggest that Jesus had them all in mind when he spoke.
Except that he probably didn’t. And, to his credit, Peter Leithart eventually gets there when he says, “Jesus’s proverb is primarily a warning about unsaltiness.” In other words, the actual effects of salt are not brought out in the text or emphasized. What is front and center is the character of the disciples. Immediately upon pronouncing them “the salt of the land,” Jesus warns them about losing that quality. Whatever it is that “salt” might have evoked in their minds, Jesus is exhorting them to be faithful to their calling. As Andrew Perriman, who also, by the way, thinks the metaphor is more likely about the negative effects of salt, comments:
. . . it would appear that the metaphor of “salt” has to do with the effect that the presence of a community of disciples, whose righteousness exceeds that of the Pharisees (cf. Matt. 5:20) and who are willing to pay the price of suffering, would have within Israel under judgment. The emphasis, however, is less on the actual impact of the community than on the need for the disciples to maintain their integrity and commitment.
, by Miroslav Volf.
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