How a person behaves is spoken of as "ways" or "paths." AT: "those whose behavior is blameless" or "those whom no one can blame for doing wrong" (See: [[rc://en/ta/man/translate/figs-metaphor]])
The way a person lives or behaves is spoken of as walking. AT: "who live according to the law of Yahweh" or "who obey the law of Yahweh." This phrase clarifies the meaning of "whose ways are blameless" (See: [[rc://en/ta/man/translate/figs-metaphor]])
This is an idiom which means intensely or sincerely. AT: "with all their being" or "with everything in them" or "sincerely" (See: [[rc://en/ta/man/translate/figs-idiom]])