What does this mean?

Question

''In literature, number seven is the number of complete order''
srry, dont get it, i'm foreign

Answer 1

It is well known that men of different times and nations have associated with particular numbers the idea of a peculiar significance and value. It is also well known that, of all numbers, there is no one which has excercised in this way a wider influence, no one which has commanded in a higher degree the esteem and reverence of mankind, than the number Seven. The mystic preëminence of this sacred number is as ancient as it is venerable. It belongs to the simple wisdom of a primitive age. It had its native home in the East, near the springs of light and of day. True, we find it also in later times, and upon occidental ground, pervading the mind and literature of modern Europe. But we must remember that an Oriental book, an Asiatic book, the Sacred Scripture of the Hebrew, has leavened--may we not add that it has sevened-- the mind and literature of modern Europe. But before this influence began, before a new religion coming into Europe from the East brought with it the Oriental feeling for the Seven, the case was widely different. Among the ancient Greeks and Romans, but little prominence upon the whole is given to this number. Let us look at the first great monuments of western literature, the poems of Homer

Answer 2

because the bible says so