What does Ruth 3:8 mean?

In this chapter, Ruth is not called by her name except when she identifies herself (Ruth 3:9). For the most part, she is identified by pronouns. She is presented as a woman on a mission to do everything she can to protect her mother-in-law.

Here, however, we pull away from the desperation of poverty, the salacious way in which some interpret the scene, and the fact that the differences in nationality and social standing make Ruth's request ridiculously presumptuous. Here we see a woman quietly speaking to a man at midnight, surrounded by the blessings of the harvest and sleeping would-be witnesses. This is not a scandalous affair; it's romance.

"Startled" may mean Boaz trembled in fear; he is lying with the grain to protect it from thieves when he suddenly realizes someone is lying at his feet. Conversely, it may mean that he shivers from the cold on his uncovered feet. "Turned over" doesn't mean Ruth is lying next to him; she is at his feet. Boaz stirs because his feet are cold or because he is startled and thus turns to look around.

When Boaz asks who this person is, Ruth identifies herself and gives him a challenge. Earlier, he had blessed her, noting that she had chosen to find refuge under the wings of God (Ruth 2:12). Ruth asks Boaz to cover her with his wings—literally, the edges of his robe, but metaphorically protection and provision for herself and Naomi—thus fulfilling his own prayer. Boaz responds with admiration that still Ruth is thinking of Naomi over herself (Ruth 3:9–10).