וַתֹּ֕אמֶר יֻתַּ֖ן אֶת־אֲבִישַׁ֣ג הַשֻּׁנַמִּ֑ית לַאֲדֹנִיָּ֥הוּ אָחִ֖יךָ לְאִשָּֽׁה׃
And she said: ‘Let Abishag the Shunammite be given to Adonijah thy brother to wife.’
Read halakhic rulings (Jewish law) on I Kings 2:21: and classical halakhic sources.