וְאִם־אֵ֣ין אַחִים֮ לְאָבִיו֒ וּנְתַתֶּ֣ם אֶת־נַחֲלָת֗וֹ לִשְׁאֵר֞וֹ הַקָּרֹ֥ב אֵלָ֛יו מִמִּשְׁפַּחְתּ֖וֹ וְיָרַ֣שׁ אֹתָ֑הּ וְֽהָ֨יְתָ֜ה לִבְנֵ֤י יִשְׂרָאֵל֙ לְחֻקַּ֣ת מִשְׁפָּ֔ט כַּאֲשֶׁ֛ר צִוָּ֥ה יְהוָ֖ה אֶת־מֹשֶֽׁה׃ (ס)
And if his father have no brethren, then ye shall give his inheritance unto his kinsman that is next to him of his family, and he shall possess it. And it shall be unto the children of Israel a statute of judgment, as the LORD commanded Moses.’
Rashi on Numbers
לשארו הקרוב אליו ממשפחתו TO HIS KIN THAT IS NEXT TO HIM OF HIS FAMILY — The term משפחה used in connection with inheritance denotes kinship only on the father’s side (Sifrei Bamidbar 134:3; Bava Batra 119b).
Ramban on Numbers
AND IT SHALL BE UNTO THE CHILDREN OF ISRAEL A STATUTE OF JUDGMENT. The meaning thereof is that this judgment should be for all [future] generations, and not only for now when they inherited the Land [hence the expression “a statute, i.e., a permanent one, for all the children of Israel in all future generations”].
Tur HaArokh
והיתה לבני ישראל לחוקת משפט, “This shall be for the Children of Israel as a decree of justice.” This will be a law from now on not only for the people that were about to enter the Holy Land.