God created certain animals that can be used for food and others that are unfit to eat. "Clean" foods are those which in their natural state do not harm the human body. "Unclean" foods are those which are unhealthy for the body.

(DEUT 14:3-21) You are not to eat any abominable thing. And these are the creatures which you can eat; the ox, the sheep, the goat, the hart, the roebuck, the fallow deer, the wild goat, the antelope, and the wild ox. And every creature that has parted hoofs or separates the cleft into to two, and chews the cud among all creatures, them you can eat. And these are those you cannot eat from among those that chew the cud, or that divide the hoof; the camel, and the hare, and the coney, for they chew the cud, but do not have a divided hoof, they are therefore unclean for you. Also the swine, because it does not have a divided hoof, even though it chews a cud it is unclean for you, you cannot eat of them. These you can eat that are in all the waters; all that have fins and scales you can eat. Anything that does not have fins and scales you cannot eat, it is unclean for you. And you can eat any clean fowl but these you cannot eat: the eagle, the ossifrage, the osprey, the glede, the kite, the vulture, the raven, the owl, the hawk, the cuckoo, the swan, the pelican, the stork, the cormorant, the heron, and the bat. And all creeping things that can fly are unclean, they are not to be eaten. All clean fowls you may eat.

(GEN 1:29)
God said, Behold, I have given you every herb bearing seed, which is upon the face of all the earth, and every fruit tree containing seeds to be your food.

 (LEV 3:17)
It will be an everlasting law for your generations in all their dwellings, that you can not eat fat or blood.

 (LEV 7:23-24)
You cannot eat any kind of fat, of ox, or of sheep, or of goat. But the fat of any animal that dies by itself or is killed by other animals, can be used for other uses but you can not eat it. 

(LEV 7:26)
Also you cannot eat any type of blood, whether it be from fowl or mammal, in any of your homes. 

(LEV ll:All) Read it all.

Below is a list of foods, defined in the Bible, as being Clean and Unclean. 

They can be found in Leviticus 11 and Deuteronomy 14.

These laws are known as health laws, and are the means for achieving a healthier life. 

In the beginning man ate fruits and vegetables, but later started eating meat. God made known what meats where unhealthy through the laws of clean and unclean foods long before there was a nation of Israel, even before Noah's time, as seen in Genesis 7:2 and 7:8.

It is a well know fact today, that these same unclean foods are known to be unhealthy.

But you say, what about the following verse from scripture?

(Deut 12:15) Notwithstanding thou mayest kill and eat flesh in all thy gates, whatsoever thy soul lusteth after, according to the blessing of the Lord thy God which he hath given thee: the unclean and the clean may eat thereof, as of the roebuck, and as of the hart.

This is one of the most misinterpreted verses on this subject, because of the food laws being well know in their nation they did not keep unclean animals around for food, so they would not have found it in their gates. It is speaking of the unclean person eating with the clean person during this time. Normaly an unclean person was not allowed to eat with those that where clean. 

(Deut 15:22) "Thou shalt eat it within thy gates: the unclean [person] and the clean person shall eat it alike, as the roebuck, and as the hart "

How clear it becomes now.

(ISA 66:17)Of them that bless themselves, or purify themselves in the gardens hiding behind a tree, eating swine's flesh, and the other abominations, such as the mouse, will be consumed together does say the Lord.

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