Is it true? No.

The Bible interprets itself. It says that salt is a sign of the Covenant; God isn’t particularly interested in preserving human cultures, his mission is to spread his culture–the Kingdom of Heaven. Followers of Jesus are to be a sign to the world of the Kingdom of Heaven—and how to get there (John 8:31,32)

Season all your grain offerings with salt. Do not leave the salt of the covenant of your God out of your grain offerings; add salt to all your offerings. Leviticus 2:13

From that time on Jesus began to preach, “Repent, for the kingdom of heaven has come near.” Matthew 4:17

Cultures are set on earthly things. But the ultimate citizenship of followers of Jesus is in heaven.

Their mind is set on earthly things. But our citizenship is in heaven. And we eagerly await a Savior from there, the Lord Jesus Christ, who, by the power that enables him to bring everything under his control, will transform our lowly bodies so that they will be like his glorious body.  Philippians 3:19-21