Leviticus 22:1-23:44

God tells the priests who can and who can not eat the meat that was offering.  Then details unacceptable sacrifices.  He ends chapter 22 with "31 Keep my commands and follow them. I am the Lord. 32 Do not profane my holy name. I must be acknowledged as holy by the Israelites. I am the Lord, who makes you holy 33 and who brought you out of Egypt to be your God. I am the Lord." 

Even today he is having to constantly remind us of who he is.  He is holy. He is the Lord.  

Chapter 23 details appointed feasts that are to be "proclaimed as sacred assemblies."  Many of these are actively observed in Jewish Synagogues in an adapted manner.  They include Passover, First Fruits, Feast of Weeks, Feast of Trumpets, Day of Atonement (Yom Kippur), and Feast of Tabernacles.