How did Spinoza use the account of Moses’s death to question Mosaic authorship of Deuteronomy?

In his work Tractatus Theologico-Politicus, Benedict de Spinoza utilized a naturalistic and historical approach to analyze the Hebrew Bible, arguing that it is a collection of writings by various authors from different eras rather than a divinely authored text.1

Spinoza specifically challenged the traditional attribution of the Pentateuch to Moses by pointing to internal inconsistencies within the text. He noted that the book of Deuteronomy, which is traditionally ascribed to Moses, contains a narrative describing Moses's own death and burial. Because it is logically impossible for an author to record their own death, Spinoza concluded that this passage—and by extension, the book itself—must have been written by someone other than Moses. This observation served as evidence for his broader argument that the scriptures should be studied as historical documents rather than as a singular, infallible divine revelation.12