And whosoever toucheth one that is slain with a sword in the open fields, or a dead body, or a bone of a man, or a grave, shall be unclean seven days.
Numbers 19:16 KJV COMMENTARY https://bible.com/bible/1/num.19.16.KJV
okay I now understand where that law regarding the Nazarite comes from because in that law God tells the Nazarite that he shall not mourn even for his own dead relative, for his parents for his siblings because in mourning definitely you would come close to them you mourm for.
You will touch the things of the dead and that would make the Nazarite unclean and per the law of the Nazarite one shall not make himself or herself unclean for the Dead.
so I get the connection now, in the sense that as you try to moan for your dead family or relative you definitely will come in contact with the Dead and if you do that would make him clean and as you see in this case uncleanliness for coming in contact with the dead is for 7 days and you are under a Nazareth vow you cannot be unclean, you cannot mourn the Dead.
Less so to think of becoming unclean for as long as 7 days 7 long days for the Dead. https://bible.com/bible/1/num.19.16.KJV