If an Israelite, or a priest sinned unintentionally, that person was to bring to the tabernacle of meeting, a bull and kill it (Leviticus 4.2–4).
Then the anointed priest took some of the bull’s blood, and,
“The priest shall dip his finger in the blood and sprinkle some of the blood seven times before the LORD, in front of the veil of the sanctuary” (Leviticus 4.6).
Nothing accidental or incidental in that action!
What the priest did here was part of the sin offering that an Israelite might receive the forgiveness of his sins.
Therefore, the Lord choose the sprinkling of the blood seven times for a reason, showing that the person’s sins had been completely forgiven for following the Lord’s wishes on this matter.