Leviticus 8:33
You will not leave the entrance to the Tent of Meeting for seven days. Do not leave until the last day of your ordination is over. It will take seven days to ordain you.
Exodus 29:35
Do to Aaron and to his sons all that I have commanded you. Ordain them for seven days.
Exodus 29:30
For seven days the one of his sons who is priest in his stead shall put them on when he enters the tent of meeting to minister in the holy place.
Leviticus 14:8
You must wash your clothes, shave off all your hair, and take a bath. You will then be ritually clean. You may enter the camp. You must live outside your tent for seven days.
Numbers 19:12
They must purify themselves with the water for purification on the third day and on the seventh day. Then they will be clean. But if they do not purify themselves on both the third and the seventh day, they will not be clean.
Ezekiel 43:25-27
Every day for seven days you must sacrifice a goat, a young bull, and a ram from the flock as an offering for sin. They must be animals that have no defects.