Salt used in Ratifying Covenants
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Numbers 18:19
All the holy offerings that the Israelites present to the LORD I give to you and to your sons and daughters as a permanent statute. It is a permanent covenant of salt before the LORD for you and your offspring.”
2 Chronicles 13:5
Do you not know that the LORD, the God of Israel, has given the kingship of Israel to David and his descendants forever by a covenant of salt?