Here "we" refers to Isaiah and the people of Israel. Isaiah is describing something in the future as if it has already happened. AT: "we will hear" (See: [[rc://en/ta/man/translate/figs-inclusive]] and [[rc://en/ta/man/translate/figs-pastforfuture]])
Isaiah repeats this phrase to emphasize his anguish. He was very concerned because he saw people who deceived others and did not do what they promised to do. AT: "I have become very weak" (See: [[rc://en/ta/man/translate/figs-parallelism]])
Isaiah repeats this phrase to emphasize his anguish. AT: "Indeed, those who deceive are now deceiving others" or "Indeed, the deceivers have acted deceitfully" (See: [[rc://en/ta/man/translate/figs-parallelism]])