Albert Barnes Commentary Ruth 4:3

"And he said unto the near kinsman, Naomi, that is come again out of the country of Moab, selleth the parcel of land, which was our brother Elimelech`s:" — Ruth 4:3 (ASV)

According to the law (Leviticus 25:25–28), if any Israelite, through poverty, were to sell his possession, the next of kin (the גאל gā'al) had a right to redeem it by paying the value of the number of years remaining until the jubilee (see the marginal reference). This right Boaz notifies the גאל gā'al of, to give him the option that the law secured for him of redeeming “our brother Elimelech’s” land—that is, our kinsman’s—according to the common use of the term brother for a near relation (Genesis 24:27; Leviticus 25:25; Numbers 27:4; Judges 9:1).