So Moses the servant of Jehovah died there in the land of Moab, according to the word of Jehovah. (ASV)
This and the remaining verses cause problem for the traditional attribution of authorship to Moses; how could he have known about his death? And how was he so sure that there would be nobody like him in all the time since?
Conservative biblical scholars believe that the part about the death of Moses was written by Joshua, who succeeded Moses as the Judge of Israel.
Even if it wasn't Joshua, it's no different than an unfinished book by a deceased author that is given an afterword by someone else, a common practice.
Also, while conservative scholars assume that the Torah was written by Moses, nowhere does it actually state that conclusively. "Moses spoke these words to Israel" and "Moses began to declare this law, saying," are not the same as "I, Moses, said these words." It would be just as possible for someone who was a contemporary of Moses to have written Deuteronomy.
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