When someone had a swelling, a scab, or a bright spot in ancient Israel, and the problem area began to look like leprosy or some other serious skin disorder, the priest examined the person, and the Lord gave these instructions,
“But if the bright spot is white on the skin of his body, and does not appear to be deeper than the skin, and its hair has not turned white, then the priest shall isolate the one who has the sore seven days. And the priest shall examine him on the seventh day; and indeed if the sore appears to be as it was, and the sore has not spread on the skin, then the priest shall isolate him another seven days. Then the priest shall examine him again on the seventh day; and indeed if the sore has faded, and the sore has not spread on the skin, then the priest shall pronounce him clean; it is only a scab, and he shall wash his clothes and be clean” (Leviticus 13.4–6; See also verses 21, 26, 27, 31–34, 50, 51, 54).
Was it simply coincidental that the two examination periods were seven days each? Did the Lord set up the human body that such skin problems would show their true nature after a seven-day examination? Did this seven-day examination symbolize anything?
It is hard to answer these questions, but the priest knew what the Lord wanted, and by following His orders, the priests would know what to do with someone in the event that a skin problem occurred.
We may not always know why things are the way they are, but if the Lord has provided instructions, commands, insight, or anything on that matter, we should follow what He directs, and then we shall have good success.