Those who touch the body of someone who has died are unclean. If they stay unclean and then go to the Lord’s Holy Tent, they make it unclean. So they must be separated from the Israelites. Because the special water was not thrown on them, they remain unclean.
“Tell the people to send away from the camp anyone who is unclean, that is, anyone who has a serious skin disease or discharge and anyone who has touched a dead body.
“If you have taken the Nazirite vow, you must not go near someone who is dying during that special time of dedication. You have given yourself fully to the Lord,
So if you are with someone when they suddenly die, you will be unclean and you will have to shave the hair from your head. You must do that on the seventh day of your purification ceremony when you are made clean.
But some of the people could not celebrate Passover that day. They were unclean because they had touched a dead body. So they went to Moses and Aaron that day