Albert Barnes Commentary Ruth 2:12

"Jehovah recompense thy work, and a full reward be given thee of Jehovah, the God of Israel, under whose wings thou art come to take refuge." — Ruth 2:12 (ASV)

The similarity of expression here to Genesis 15:1, and in Ruth 2:11 to Genesis 12:1, makes it probable that Boaz had the case of Abraham in his mind.

The Lord God of Israel - "Jehovah the God of Israel." Compare Joshua 14:14, where, as here, the force of the addition, the God of Israel, lies in the person spoken of being a foreigner (see Judges 11:21 note).