Here "my bones" represents the body of the writer. AT: "my whole body is diseased because of my sin" (See: [[rc://en/ta/man/translate/figs-synecdoche]])
The writer's iniquities are spoken of as if they are a flood of water that covers him. AT: "my iniquities cover me like a flood" (See: [[rc://en/ta/man/translate/figs-metaphor]])
The writer's iniquities are spoken of as if they are a heavy load that he cannot lift. AT: "they are like a load that is too heavy for me to lift" (See: [[rc://en/ta/man/translate/figs-metaphor]])