TSK · Ruth 3:2

If brethren dwell together, and one of them dye & haue no sonne, the wife of the dead shall not marry without: that is, vnto a stranger, but his kinseman shall goe in vnto her, and take her to wife, and doe the kinsemans office to her.

Then said Boaz vnto Ruth, Hearest thou, my daughter? goe to none other fielde to gather, neither goe from hence: but abide here by my maydens.

For he that sanctifieth, and they which are sanctified, are all of one: wherefore he is not ashamed to call them brethren,