The Number “7” Seven

Also considered as Lucky Number (by many people)
I have just noticed, after a few research, that the number 7 is the most significant of all numbers. In Islam, 7 is used in many places, examples are many but here are some:

-The number of verses in the first Surah (Al Fatihah) is 7
-There are 7 Heavens, many verse in Quran about that
-7 layers of the Earth according to Quran
-Hell has 7 doors and 7 grades.
-Quran 15:87 “And We have certainly given you, [O Muhammad], seven of the often repeated [verses] and the great Qur’an.”
-Stoning Iblees 7 times
-In Makka, the number of Tawaaf (circumambulations) around kaabah is 7
-The number of walks between Al Safa and Al Marwah mountains is 7 times during Hajj and Umrah
-The Prophet Yusuf (pbuh) was asked to interpret the King’s dream where 7 fat cows were dreamt to have been devoured by 7 skinny cows and 7 green spikes, and others shriveled.
-Sujud (Prostration) is made by 7 parts of the body; 2 feet, 2knees, 2 palms and a face.
-There 7 types of recitations of the Quran.
-Hadith: “When a dog licks a vessel of any of you, he should wash 7 times. (Inshaallah in the next posts we’ll talk about this Hadith and what’s behind washing it 7times.)
-Hadith about (types of) people whom Allah will keep under His shade the day, in which, there will be no any other shade accept His shade.(The whole Hadith should be in the first comment, inshaallah)

There are many examples as I said and some of them don’t mention the exact number 7, as in:
-Surah Tawbah 180; “Even if you ask for them forgiveness (from Allah) 70 times, Allah will not forgive them”

-Windows 7
-James Bond’s 007
-7 days a week
-BMW 7 Series
– Film “Seven Pounds” starring Will Smith
-Shakespeare’s 7 Ages of Man theory
-The novel “Seven Days in May”, by Fletcher Knebel
-“The Sevens” a rugby union stadium in Dubai.
-The number 7 appears commonly in the Bible too;
+Seven days of Creation (Genesis 1)
+Seven days of the feast of Passover (Exodus 13:3–10)
-Seven Promises, Seven Rounds in Hindu Wedding and Seven Reincarnation
-There are 7 types of virus according to the Baltimore classification
And many more…

But why 7? Allah knows best.