What does the number 7 represent in Christianity?

Taking the number 4 from the 4 corners of the world plus the number 3 from the Holy Trinity-Father, Son and the Holy Spirit. Makes number 7. This number means completeness, perfection. Other examples in the Catholic Bible which includes the number 7: -7 days of creation (including the day of rest) -7 holy sacraments -7 virtues -7 deadly sins -Jesus saying to forgive others 77 times, not literally but it emphasising on the fact that we should always forgive. There are more examples on http://en.wikipedia.org/wiki/7_(number)#Christianity