"And, behold, I, even I, do bring a flood of waters upon the earth, to destroy all flesh, wherein is the breath of life, from under heaven; and every thing that is in the earth shall die. But with thee will I establish my covenant; and thou shalt come into the ark, thou, and thy sons, and thy wife, and thy sons' wives with thee. And of every living thing of all flesh, two of every sort shalt thou bring into the ark, to keep them alive with thee; they shall be male and female. Of fowls after their kind, and of cattle after their kind, of every creeping thing of the earth after his kind, two of every sort shall come unto thee, to keep them alive. Thus did Noah; according to all that God commanded him, so did he."(Genesis 6:17-22)
This is the story of Noah that most people know. The nursery rhyme even goes 'Noah brought the animals 2 by 2'...
Noah only brought two of each animal because only two is needed to procreate.However, this is not the end of the story; it continues.
"And the LORD said unto Noah, Come thou and all thy house into the ark; for thee have I seen righteous before me in this generation. Of every clean beast thou shalt take to thee by sevens, the male and his female: and of beasts that are not clean by two, the male and his female. Of fowls also of the air by sevens, the male and the female; to keep seed alive upon the face of all the earth. For yet seven days, and I will cause it to rain upon the earth forty days and forty nights; and every living substance that I have made will I destroy from off the face of the earth. And Noah did according unto all that the LORD commanded him." (Genesis 7:1-5)
Noah originally brought two of every animal. Then in the next chapter we see that he brought 7 of every 'clean' beast. And two of every unclean beast.
What is it that makes an animal clean?
"These are the beasts which ye shall eat among all the beasts that are on the earth. Whatsoever parteth the hoof, and is clovenfooted, and cheweth the cud, among the beasts, that shall ye eat. Nevertheless these shall ye not eat of them that chew the cud, or of them that divide the hoof:
as the camel, because he cheweth the cud, but divideth not the hoof; he is unclean unto you.
And the coney, because he cheweth the cud, but divideth not the hoof; he is unclean unto you.
And the hare, because he cheweth the cud, but divideth not the hoof; he is unclean unto you.
And the swine, though he divide the hoof, and be clovenfooted, yet he cheweth not the cud; he is unclean to you...
For I am the LORD that bringeth you up out of the land of Egypt, to be your God: ye shall therefore be holy, for I am holy.
This is the law of the beasts, and of the fowl, and of every living creature that moveth in the waters, and of every creature that creepeth upon the earth:
To make a difference between the unclean and the clean, and between the beast that may be eaten and the beast that may not be eaten." (leviticus 11:1-47)
So when Noah brought the 'clean' animals into the Ark (the animals that are permissible to eat), he brought those by 7's not by two.
"And God spake unto Noah, saying, Go forth of the ark, thou, and thy wife, and thy sons, and thy sons' wives with thee... And Noah went forth, and his sons, and his wife, and his sons' wives with him: Every beast, every creeping thing, and every fowl, and whatsoever creepeth upon the earth, after their kinds, went forth out of the ark. And Noah builded an altar unto the LORD; and took of every clean beast, and of every clean fowl, and offered burnt offerings on the altar.
And the LORD smelled a sweet savour; and the LORD said in his heart, I will not again curse the ground any more for man's sake; for the imagination of man's heart is evil from his youth; neither will I again smite any more every thing living, as I have done. While the earth remaineth, seedtime and harvest, and cold and heat, and summer and winter, and day and night shall not cease."
For sacrifice. Thanksgiving sacrifices for sparing Noah and his family. You can only sacrifice 'clean' animals to the Lord. Therefore Noah knew the Laws of God and was obedient, that is why he brought 7 clean animals so that he could sacrifce one or two to the Almighty.
Notice also how those sacrifices created a sweet smelling savour to the Lord. Maybe God is black (he likes the smell of Bar-B-Que. :) lol