“You are

The salt of the earth!

But if salt

Has lost its taste,

How can saltiness

Be restored?

It is no longer good

For anything,

But is thrown out.

It is trampled

Under foot.”

Ὑμεῖς ἐστε τὸ ἅλας τῆς γῆς· ἐὰν δὲ τὸ ἅλας μωρανθῇ, ἐν τίνι ἁλισθήσεται; εἰς οὐδὲν ἰσχύει ἔτι εἰ μὴ βληθὲν ἔξω καταπατεῖσθαι ὑπὸ τῶν ἀνθρώπων.

This saying of Jesus can be found in Mark, chapter 9:49-50, and Luke, chapter 14:34-35, but not connected to the Beatitudes at all and with different phraseology. Salt was important not just as a spice and preservative but it represented wisdom and purity in the ancient world and Judaism. Matthew has Jesus turn to his disciples to remind them that they are the salt of the earth or the land (Ὑμεῖς ἐστε τὸ ἅλας τῆς γῆς). Meanwhile, the other two gospel writers just had statements about salt, rather than speaking explicitly to the disciples. Matthew then switched to the 3^rd person from the 2^nd person, when he explained about salt losing its taste (ἐὰν δὲ τὸ ἅλας μωρανθῇ). How can the taste be restored to the salt (ἐν τίνι ἁλισθήσεται)? That salt was now useless, impotent, and not good for anything (εἰς οὐδὲν ἰσχύει ἔτι). The end result of this tasteless salt was that it should either be thrown away (εἰ μὴ βληθὲν ἔξω) or have people trample it down (καταπατεῖσθαι ὑπὸ τῶν ἀνθρώπων).