Q: I am in a very wonderful class this year — a class that studies early world history by comparing and researching different religious texts. I was looking through my Bible, and in Genesis, Chapter 7, I found that there were actually seven pairs of “clean” animals [on Noah’s ark], which was a shock to me, as I was raised on cartoon Bible stories thinking that there were only two. My questions: Why are there seven clean pairs of animals, but only one unclean pair? Why are some animals considered unclean? On that note, are birds considered clean, or are they just special? Finally, with all of the number 7’s, is there significance that this is in the seventh chapter, or is it just a coincidence? Thank you very much for your answer! -C.S.

Answered by Fr. Edward McIlmail, LC

A: It is good that you have such interest in the Bible, which is the inspired word of God.

The cartoons you remember might have been inspired by Genesis 6:20, where God initially gives a general order to bring two animals of each kind — “Of every kind of bird, of every kind of animal, and of every kind of thing that crawls on the ground, two of each will come to you, that you may keep them alive.”

In Genesis 7:2, God gives an additional order — to bring seven pairs of clean animals and birds. The reason becomes clear after the flood subsides. The initial pair of each animal from 6:20 will assure that the world is repopulated after the flood with all the different species of animals and birds.

As regards the seven pairs, in Genesis 8:20, after the flood subsides Noah offers to God a sacrifice of some of the clean animals: “Then Noah built an altar to the LORD, and choosing from every clean animal and every clean bird, he offered burnt offerings on the altar.”

By having taken seven pairs of the clean animals and clean birds on the ark, Noah is able to offer a sacrifice to God of those clean animals while still allowing those species to repopulate the earth.

So, in this context, clean animals were animals that were considered apt to sacrifice to God. Beyond that, why are some animals considered clean and others not? That is a difficult question. There are many theories, including hygiene. Some birds were considered clean, but others (such as birds of prey) were considered unclean. For more reading see the Jewish Encyclopedia entry.

Is there something significant about the reference to “seven” appearing in Genesis 7? Probably not, since chapter numbers weren’t affixed to Scripture until the Middle Ages (see here).

I hope some of this helps. God bless.