“my daughter.” Boaz sees Ruth as young enough to be his daughter, but realizing her welfare is at stake is willing to marry her.
“do not be afraid.” Boaz understood perfectly that Ruth (and Naomi) had reasons to worry about their future, and Boaz speaks directly to that to calm Ruth’s mind.
“I will do for you all that you say.” This demonstrates true humility on the part of Boaz, even in making the statement the way he did. Doing “all that you say” is generally the role of the servant, listening to the master, but here Boaz understands the need that Ruth and Naomi have, he understands his kinship relation to them, and he understands the wisdom in Ruth’s being married to him, so he makes the simple and humble statement, “I will do for you all that you say.” A man with more insecurity and pride might have understood Ruth’s need but have spoken to her differently.
“for all the gate of my people knows.” The word “gate” is a metonymy for the people of the gate, both the gossips and the elders, and the elders at the gate were the authorities in many cities. We now know for sure what we might have expected earlier, that Ruth had been a topic of discussion around the whole town. If “all the gate,” the elders and the gossips, knew that Ruth was a woman of noble character, then she must have been discussed and debated at some length, and certainly with some people “for” her and some “against” this Moabite girl. But in the end, her faithful devotion to Naomi and her quiet and respectful way of being had won over the people of Bethlehem such that now “all” the people (likely a hyperbole for the vast majority) understood that she was a noble woman. Since it was just now the end of the barley harvest, and Ruth came to Bethlehem at the beginning of the barley harvest, it likely took 4 to 6 weeks for people to reach that opinion.
There is a great lesson in how Ruth behaved when she knew—and she would have known—that the town was talking about her. It can be very uncomfortable to know that people are talking about you, but that is often an unavoidable part of life for those who do anything noteworthy. Ruth sets a sterling example of what to do and what not to do in that situation. Ruth just kept on doing what she needed to do, working to support her and Naomi. She did not go around the town trying to run interference for herself and influence public opinion in her favor.
“you are a woman of noble character.” The word translated “noble character” is used here and in Proverbs 12:4 and 31:10.