Just like there are 6 Firmaments of the Heavens and a 7th containing the Waters above… God made 6 parts of the Earth and the 7th part Water.
7 Days of the Week, 7 Colors of the Rainbow, Cain would be avenged 7 fold, 7 of each Clean Animal on the Ark, Lamech lived 777 years, Jacob served 7 years for Rachel, Joseph saw 7 years of famine, 7 Days of Unleavened Bread, 7×7 years in a Jubilee, 7 Lamps on the Menorah, 7 Day Priestly Ordination, Remission of Debt every 7 years, Jesus turned 7 loaves of Bread into enough to feed 4,000 with 7 large baskets of bread leftover, 7 Archangels to the 7 Churches, 7 Trumpets, 7 Bowls of Wrath, with the 7 Plagues and 7 Seals…
In Hebrew, the word “seven” is spelled with the same consonants as the Hebrew word for “complete/full”: שבע