Exodus 31:13 Speak thou also unto the children of Israel, saying, Verily my sabbaths ye shall keep: for it is a sign between me and you throughout your generations; that ye may know that I am the Lord that doth sanctify you. 24 I MC VC

Ezekiel 20:12 Moreover also I gave them my sabbaths, to be a sign between me and them, that they might know that I am the Lord that sanctify them. 18 I MC VC