This passage mainly describes the clean and unclean food the Israelites are allowed to eat. Starting with the land animals and insects, then the sea life, and lastly the birds in the air, the Lord instructs them carefully in much detail what they can eat and cannot eat, touch and not touch. Why this realm of self-denial involving food?
Eating involves fellowship and even religious worship. Just as God forbade them to eat from the tree of the knowledge of good and evil, he forbade his people to eat certain foods. Unclean food was associated with pagan religions and cultures. Eating or not eating certain foods sets them apart from other godless peoples. For example, eating cows would have made them detestable to the Egyptians, who regarded cows as sacred. By not eating pigs, it would separate them from Egyptians and the Canaanites, who ate pork.
Sharing a meal unites us emotionally, mentally, and even spiritually with others. Thus, God commands them not to touch unclean food, so that they won't be even tempted to go near them. "Be holy as I am holy'' forced them to control their appetites and set boundaries in their relationships. This would preserve them as God's holy people in history.
Application: Father, I need your discipline to be holy and sanctified. Please help me to control myself.
One Word: Be holy as I am holy