The answer is: Moses

Deut 1:1

The book of Deuteronomy is fascinating for many reasons, not just because Moses is the primary narrator, but also for the context in which it was written. This book represents the final speeches of Moses as he addresses the Israelites before they enter the Promised Land. It’s like the ultimate farewell address, filled with teachings and reiterations of the law.

One cool thing is that Deuteronomy means "second law," which makes perfect sense considering this book revisits and updates many of the earlier laws given in Exodus and Leviticus, packaged in a way that forms a solid foundation for the Israelites’ life ahead. It calls for loyalty to God, social justice, and personal responsibility—principles that resonate across generations.

Also noteworthy is the setting; Moses delivers his message amid the plains of Moab, just east of the Jordan River. Picture it! A bustling tribe, poetic speeches floating through the air, the Jordan glistening close—a dramatic backdrop as the Israelites transition from wanderers in the desert to settle into their new life.

Interestingly, Deuteronomy is famed for the Shema—a crucial piece of Jewish prayer found in Deut 6:4-5, reminding of the commitment to God: "Hear, O Israel: The Lord our God, the Lord is one." This verse is aged and treasured, reverberating through history not only in Judaism but affecting Christian thoughts about single divinity too! Such a rich tapestry of teachings and stories exists in the pages of this profound text.