This is a reference to the disciples who were standing next to Christ (see Matthew 5:1–2). They will be officially sent out by Jesus (Matthew 10:1–8; Matthew 28:19–20). “You” emphasizes that only the disciples will be the salt (and light), which excludes others such as the Pharisees, scribes, and the false prophets.1
13 “You are the salt of the earth, but if salt has lost its taste, how shall its saltiness be restored? It is no longer good for anything except to be thrown out and trampled under people’s feet.