Genesis 7:2-3 and Genesis 6:19-20
- Two (Genesis 6:19-20)--"And of every living thing of all flesh, you shall bring two of every kind into the ark, to keep them alive with you; they shall be male and female. 20Of the birds after their kind, and of the animals after their kind, of every creeping thing of the ground after its kind, two of every kind will come to you to keep them alive."
- Seven (Genesis 7:2-3)--"You shall take with you of every clean animal by sevens, a male and his female; and of the animals that are not clean two, a male and his female; 3also of the birds of the sky, by sevens, male and female, to keep offspring alive on the face of all the earth."
Genesis 6:19-20 simply instructs Noah to preserve two of every kind. Genesis 7:2-3 is additional information where seven of the clean animals were to be taken and two of every other kind. The reason for this is that the extra animals were for sacrifice. "Then Noah built an altar to the LORD, and took of every clean animal and of every clean bird and offered burnt offerings on the altar." (Gen. 8:20).
Logically, to have seven pairs also means that there are two pairs since the two are included in the seven. If one verse said take only one pair and another verse said seven pairs, that would be a contradiction.