Indeed, Ibn Ezra is claimed by proponents of the higher biblical criticism of the Torah as one of its earliest pioneers. Baruch Spinoza, in concluding that Moses did not author the Torah, and that the Torah and other protocanonical books were written or redacted by somebody else, cites Ibn Ezra commentary on Deuteronomy. In his commentary, Ibn Ezra looks to Deuteronomy 1:1, and is troubled by the anomalous nature of referring to Moses as being "beyond the Jordan", as though the writer was oriented in the land of Cana'an (west of the Jordan River), although Moses and the Children of Israel had not yet crossed the Jordan at that point in the Biblical narrative. Relating this inconsistency to others in the Torah, Ibn Ezra famously stated, "If you can grasp the mystery behind the following problematic passages: 1) The final twelve verses of this book Deuteronomy 34:1–12, describing the death of Moses, 2) 'Moshe wrote song on the same day, and taught it to the children of Israel' 31:22; 3) 'At that time, the Canaanites dwelt in the land' 12:6; 4) '... In the mountain of God, He will appear' 22:14; 5) 'behold, his king of Bashan bed is a bed of iron it not in Rabbah of the children of Ammon?' you will understand the truth."Spinoza concluded that Ibn Ezra's reference to "the truth", and other such references scattered throughout Ibn Ezra's commentary in reference to seemingly anachronistic verses, as "a clear indication that it was not Moses who wrote the Pentateuch but someone else who lived long after him, and that it was a different book that Moses wrote". Spinoza and later scholars were thus able to expand on several of Ibn Ezra's references as a means of providing stronger evidence for Non-Mosaic authorship.