Ruth being new to the Hebrew customs knows not how to “make the move” on Boaz. Naomi sees it plain as day on her face and tells her what she must do to achieve what she wants. Naomi also knows the sadness Ruth feels without a man and with the hard work she is doing day by day to provide for herself and for Naomi, she feels sympathy for Ruth. As Boaz would be the next kinsman to do his duty by Hebrew law he could take in Ruth if she asked it. Naomi tells Ruth how to do it and where so as to give him the utmost respect and privacy for his decision. Boaz was separating the barley on the threshing floor. Separating the grain from the chaff. Just as Christ does for us - “the flail strength of man”. A thing to remember every time we harvest crops of any kind. This work is the work that keep us close to Christ as it is also with His creation.
Ruth obeys every instruction that Namoi gives to her. This level of obedience is what we should strive for with Christ. Listen to His Word and live is His grace and mercy.
When Ruth had one these things, Boaz says yes! But, only if the next in the line says no, for that is not him! In the morning they will solve this issue with the man. They rest in the same manner of which they awoke with Ruth at his feet. Because of the location with which Ruth took her actions, Boaz was grateful and loving towards her. Boaz gives her 6 measures of barley from the length of her veil. No small amount. Ruth returns and recounts the events to Naomi. And give Ruth assurances that this will be handled very soon.
Boaz and the other man are the different versions of the Covenant. Boaz takes us as we are, despite our faults and shortcomings. The other man signifies the old Law. In this we will always fall short. Praise God for the new Covenant and repent our sins so we may be saved.