What is the significance of salt in the Bible? Why are the disciples of Jesus called the salt of the earth (Matthew 5:13)? This study argues that there are four central notions that stand out. The binding factor is the biblical idea of covenant. The article proceeds with a survey of salt in the Hebrew Scripture and the disciples as salt in the New Testament. Relevant texts in the New Testament include Mark 9:49–50, Luke 14:34–35, Acts 1:4, and Colossians 4:6.